Indelible
by Dmarx
Summary: Years pass and memories fade with time but his words never will. Because he wrote them down, every chapter of their story inked across the page for eternity. Sequel to Spiral Bound.
1. Chapter 1

_I started this fic about 5 years ago, and it was intended to be non-episode-specific snapshots from the Spiral Bound universe. Then I decided to include chapters for season 6 episodes, and I wrote myself into a corner trying to weave canon with this AU, and I got frustrated and gave up and deleted the whole thing from FFN. But I stumbled across it on my laptop recently and decided I should give it another try __– __without focusing on episodes this time. It's many years overdue, but I hope you guys enjoy it all the same. _

_As a reminder: this series goes AU from just before the ending of 'Watershed' and – with the exception of 'Veritas' and 'Resurrection'/'Reckoning' – will completely ignore the events of seasons 6-8_

_Disclaimer: The show has been over for three years now. I think it's safe to say that the only thing I own is my inability to stop being obsessed with these characters._

* * *

**Indelible**

**December 13, 2015**

"Hey."

Castle lifted his head, a smile bursting from his lips, crinkling the corners of his eyes as his wife walked into the room. Her hair was still damp from their shower, dark waves falling around her shoulders. She wore a long, baggy t-shirt, one she'd stolen from him two years ago and never relinquished her hold on, and nothing else, her legs completely exposed as she crossed to the bed, perched on the edge and curled her legs beneath her.

"Hey," she replied with a grin, hand coming to rest on his outstretched leg. "Whatcha doing?"

"Thought maybe we could read," he suggested, lifting one hand to reveal the front cover of their journal.

"Mmmm, it's been a while."

He raised an eyebrow, smirked. "Unless you had other plans?"

"Castle."

"What?" he asked, eyelashes fluttering innocently, and Kate had to suppress the urge to roll her eyes at him.

"It's been half an hour. Tops."

"So?"

"And before that was up against the door," she reminded him.

"I fail to see what the problem is here."

This time, she actually did roll her eyes.

"You know, it's your fault," he protested.

"What is?"

"You wore that shirt today."

"What about it?" she asked with a saucy smile. She wouldn't admit it, but she may have slipped it on this morning knowing full well how much Castle enjoyed the way the fabric hugged her curves and revealed just enough cleavage to be teasing but not too much as to be unprofessional.

He gestured across the room to the pants tossed haphazardly on the floor, one leg inside out, the other bunched up. "And those jeans."

"So?"

"So you can't dress like that and expect me to keep my hands off you."

"I'm not dressed like that anymore," she reminded him mischievously.

"Oh, I know," he assured her, voice low and sexy. He reached out with his free hand to tug on the bottom of her shirt, urge her closer. "And I think I like this outfit even better."

"Castle."

"What?"

"It's been half an hour," she repeated.

"So?"

"So some of us need a few minutes, stud," Kate offered, patting his knee.

"Right."

To say they'd been throughly enjoying married life would be an understatement.

Kate smiled, settled into the bed until she was seated next to him, back resting against the headboard. "Come on," she suggested lightly. "Let's read."

_September 8, 2015_

_Dear Kate,_

_We're married._

_I still can't believe it. I don't think I'll ever be able to say those two words without making myself completely giddy. We're married. We're spending the rest of our lives together. _

_As I write this, you're in bed next to me, sprawled on your stomach with the sheet resting across your lower back. Your head is tilted towards me, and when I first woke I just laid there for a good ten minutes watching you sleep. I know you say it's creepy, but I can't help myself. You're so beautiful. _

_And you're the first thing I see every morning. There__'__s absolutely no better way to start my day. Every day, for the rest of our lives._

_I'm so excited, Kate. I'm so excited for what lies ahead for us. At the same time, I want to savor every moment, every memory, because they're all so special to me. I don't want to forget a single detail. Not that I ever could. I can't forget anything when it comes to you. I couldn't even if I tried. That's how strong of a grip you have on my heart. _

_It's never been like this before. I know we both had our doubts. I've done this whole marriage thing before – twice – and it didn't work out either time. I know that was a difficult thing for both of us to understand, and maybe I was never able to truly find the right words to explain it to you, but now I know why: there are no words. I've tried and tried to put into words how much I love you and all the reasons I love you, and I just can't do it. There are no words to describe the way I feel right now. None at all. That's how I know, without a doubt, that marrying you was the best decision I've ever made. It's how I know that this time, when I said, "I do," I truly said it for the right reasons._

_I love you. So much._

_I could go on and on, I'm sure, because just looking at you brings forth a flood of feelings and the ring on my finger makes me so happy and the second band on yours makes me smile so hard my cheeks hurt. _

_This is quickly turning into a really long, rambling, sappy love letter, and we're in Italy and you're naked next to me and it's our honeymoon, and I'm pretty sure I can think of a few other things I'd like to do at the moment. But I had to write to you this morning, because I can't think of any other way to accurately convey how I feel. _

_I don't know when I'll write next as I'm sure we'll be quite – busy – for the next two weeks. Until then, I hope you're enjoying our honeymoon as much as I am, and I hope you don't mind if we don't leave for our day of sightseeing until this afternoon. I have other plans for us this morning, Mrs. Castle._

_Love,_

_Rick_

Kate rolled her eyes at his last sentence but the gesture was sweet and affectionate. She hadn't legally changed her name, wasn't planning to, but she actually kind of loved it when he called her by his last name.

"Mrs. Castle," he murmured, almost as though he was reading her mind.

"Hmmm?" she replied automatically.

"I like the sound of that."

Her answering smile was radiant.

"We're married," Castle spoke in awe, voice breathy and amazed.

"I know."

"I still don't think it's completely sunk in."

She shook her head in agreement. Sometimes she still woke in the morning feeling as though it was a dream. She was married to Richard Castle. Her favorite author, her partner, her best friend.

Her husband.

"Honestly," Kate began after a minute, a tint of a question in her voice, as though waiting for his approving nod before continuing. "I don't even remember most of it."

"The wedding?"

She nodded.

"Neither do I," he admitted.

"There was walking down the aisle, and there were our vows."

"And our first kiss as husband and wife," he recalled with a tender smile.

"Mmmm," Kate acknowledged.

"Our first dance."

She smiled at the memory, Castle's arms laced around her back, hers looped around his neck. He'd kissed her softly as he first drew her into his arms, holding her close as he rested his forehead against hers, neck tipped forward to make up for her lack of shoes. She thought she remembered him whispering something to her about loving when she was barefooted and shorter than him, but it might have been her imagination.

She remembered them purring sappy sentiments into each other's ears as they swayed to the music, the notes floating through the air over the background of the crashing waves. She definitely remembered the way he'd allowed his arms to span out about halfway through the song, one settling into the arch of her spine, the other coming to rest across the bare skin of her upper back. His touch alone had sent a shiver wracking through her body, coaxing a sharp exhale from his lungs at the feeling of her rippling against him.

She was fairly certain he'd had to stop himself from unhooking her dress right then and there.

"You shoved cake in my face," Castle continued, pulling her from the sensual memory.

"You smeared frosting all over me first," she countered.

"I was being decorative."

"You were being a four-year old."

He smiled innocently, and she couldn't help but roll her eyes at the next words that left his mouth. "And you're stuck with me forever."

She whacked his chest but he was faster, capturing her hand before she could pull away, sliding his fingers into the gaps between hers as he gently pressed her palm flat against his chest.

"That I am," she whispered in agreement, the thought making her heart overflow with love.

If someone had told her six and a half years ago that she'd end up marrying the man who drove her absolutely crazy with his insistence on following her around and sticking his nose into everything and arrogantly parading around like a cop, she'd have snorted in disgust and had them committed.

And yet here she was, heart irreversibly twined with his, lives mingled into one.

Forever, with Castle.

* * *

_Thoughts?_


	2. Chapter 2

_Reminder that in this universe the events of season 8 didn't happen._

* * *

**Veritas**

**January 22, 2016**

"Hey, Castle?"

He appeared in the doorway on cue, boxers slung low on his hips, t-shirt in hand. He was silhouetted against the light in the bathroom, and Kate was momentarily distracted by the sight, the strong outline of his body.

Castle was smirking when she finally dragged her eyes up to his face, eyes twinkling smugly. "Yes, _Detective_?" he husked.

"I, uh," she swallowed, forced herself to look away. Her eyes dropped to her hands, catching sight of the notebook clutched in her grasp, and only then did she remember the question she'd been planning to ask.

Right. Focus, Kate.

"Did we miss some?"

"Miss some…?"

She nodded downward to their journal. "Letters."

Castle shrugged the shirt over his head as he crossed the room, came to a stop next to the bed. "I didn't think so."

Kate flipped open to a page near the end of their first journal, held it up for him to examine. "This doesn't look familiar."

Castle skimmed the words, and though he remembered writing it, he didn't recall them ever reading or discussing it. "Maybe we did."

"The day of our wedding…"

"You found my letter," he recollected.

"And you read mine."

"And we kept reading from there, didn't we?" he asked, brow furrowed.

She nodded. "I think so."

Castle climbed into bed, sliding across the mattress and extending his legs beneath the blankets as his back came to rest against the padded headboard. "In that case, care to do some reading?"

Kate settled against his side, warm and cozy in stark contrast to the blizzard that raged outside. "Don't mind if I do."

Together, they lost track of time, drawn in by Castle's words, reminiscing about things past as they read his letters one page at a time. Both had completely lost count of the number of pages they'd covered by the time they stumbled upon the entry from a very memorable date: the day the man behind Johanna Beckett's murder was finally taken down.

_May 5, 2014_

_Dear Kate,_

_I don't think I have the words to write to you today. I'm just so damn proud of you and I'm so happy for you. More than anything and anyone else in the world, you deserve this. You deserve justice._

_I remember during the Dick Coonan case, you told me you'd let your mother down. I never thought it was true, but I know you believed it. But knowing who you are and how hard you fight for answers – not just your own, but answers for every single victim – you could never let your mother down. It's impossible. Speaking as a parent, I know she'd be so unbelievably proud of you every single day. _

_I know that today, she's up there smiling down at you and shedding tears of joy._

_You're incredible, Kate. The way you carried yourself today was amazing. What you accomplished today was remarkable. __I've never been more proud to stand by your side._

_And I love you more than words can ever convey._

_Rick_

"We did it," she whispered as she reached the end of the letter, the words caught in her throat.

It had been a long and harrowing process following Bracken's arrest; his arraignment, court hearings, and finally the multi-day trial, leaving the entire team at the Twelfth – but especially Kate – utterly burned out and exhausted.

But it was over, Bracken sentenced to life in prison, and the constant threat of death lifted from her shoulders. She hadn't realized just how much it had been weighing her down until it was gone.

"We did it," Castle echoed, tightening the arm draped across her shoulders, pressing her into his side.

Kate came willingly, curling her legs and allowing her bent knees to fall to his thighs as her cheek came to rest against his collarbone. Castle set the journal aside, found her right hand with his left and twined their fingers together against his chest. He pressed a kiss to the top of her head, exhaled softly.

There wasn't any more to say. They'd been through it all together, side by side, and rehashing it now would serve no benefit. This case had torn them apart on multiple occasions, was the catalyst for some of their nastiest fights. But in many ways, it had also brought them closer, and they were stronger because of it.

They were more solid now than they'd ever been.

And it was finally over.

* * *

_Thoughts?_


	3. Chapter 3

_Thank you to everyone who has read, reviewed, tweeted, reblogged links, etc._

_Also, thank you as always to Andy, who has put up with about 8 months of me complaining and getting stuck and sending her half-finished chapters and writing this fic completely out of order. Somehow, she always manages to have the suggestions that help me turn jumbles of words and ideas into a coherent story._

* * *

**Resurrection & Reckoning**

**February 23, 2016**

"You know, we haven't read in a while," Kate mentioned as they settled into bed.

For such a short month, February was dragging on; it'd been cold, cloudy, and snowy for much of the past two weeks, and Kate shivered and jerked her leg away as it came into contact with her husband's icy feet. Even the warmth of the loft wasn't enough to banish the never-ending winter.

When Castle didn't reply, she turned her eyes to him, found him hesitant, unsure.

"Rick?"

"I know what the next letter is," he confessed. "I've been avoiding it."

"It's bad?"

He nodded solemnly.

"What is it?"

He reached for her hand, twined his fingers with her own and held on far more tightly than necessary. Grounding himself, she assumed.

"3XK," he finally uttered, the syllables barely more than a broken whisper. "The very last time."

Oh.

Well, she certainly understood his evasiveness.

"We can skip it," Kate suggested hesitantly. She didn't want to skip it. Well, that wasn't entirely accurate. She was in no hurry to relive any portion of the 3XK saga, particularly the final, horrifying chapter. But she was equally reluctant to skip a letter, to leave his words unread. After all this time, all the pages they'd made their way through together, it was a streak she couldn't bring herself to break.

"Or you can skip it," she amended. "I can read it alone."

"No." His protest was instant. "If you're going to read it and relive it, I am too. You're not in this alone, Kate."

Castle lifted the notebook from his nightstand while Kate steeled herself, prepared her mind to be transported back to the horrors from just over a year ago.

"You ready?" he asked as he smoothed down the page, propped the journal against his bent knees.

She nodded, feigning more courage than she felt. "Ready."

_February 17, 2015_

_Dear Kate,_

_I wasn't sure I'd be writing this letter today. I wasn't sure I'd be writing anything ever again. _

_I know you don't need a reminder of what happened, and neither do I, but they took you. Tyson and Nieman. You were missing for two days, and I completely lost it. I couldn't think straight. I couldn't sleep. I couldn't eat. I desperately needed the caffeine but without you sitting next to me cradling your own mug of coffee, the smell of it made me nauseous. _

_After two divorces, Montgomery's funeral, Paris, and all the other close calls we've had over the years, I thought I could handle anything. It turns out I can't handle losing you. I don't think I've ever been so broken in my entire life. I threatened an unarmed man with a gun. I put myself in a position of certain death. Looking back now, I hardly recognize the man I became. I was reckless and desperate and willing to do absolutely anything I could to find you._

_I wish I didn't have to admit this, but I understand you better now. I understand your single-minded obsession with your mother's case. I understand why you fought with me and kicked me out of your life every time I tried to get you to walk away. I understand your willingness to put yourself in the crossfire for someone you love. If anyone had come to me while you were missing and told me to take a step back and stop looking for you, I'd have reacted exactly the same way. _

_It scares me, the decisions I made and the way I behaved. But the thought of living without you scares me even more. _

_I'm infinitely grateful to have you back and I'm so glad you're unharmed – relatively speaking. I know it will be a while before the trauma of this ordeal truly manifests, and even longer before we come to grips with it, but physically we're both okay and we're safe and that's what matters. _

_But most of all, I'm sorry. I'm so sorry I wasn't there to protect you. I'm sorry I didn't find you sooner. I'm sorry you had to suffer through such horrors. _

_I know right now you're still reeling, and so am I. Why else would I be writing this at 3:47am? I'm utterly exhausted but I can't sleep, and I know when I finally do I'll be plagued with nightmares. I know you're experiencing them too. You already woke once tonight sweating and shaking and gasping for air. _

_I have a feeling it's going to be a while before things start to feel normal for us again. Sometimes I'm not sure what 'normal' is anymore. But I'm here for you. Anything you need, anything I can do, I'm here. I wasn't able to protect you when you needed it most, but I'm damn well going to be here for you now. _

_I love you, Kate. I love you with a fierceness I'm not sure I knew existed until this week._

_Rick_

"I can't believe that was a year ago," she murmured, the most benign comment she could muster given what they'd just read.

"It seems like a lifetime ago," Castle agreed. And yet, whenever the nightmares resurfaced it seemed much more recent.

"Do you ever think back on our past and feel like you're on the outside looking into someone else's life?" Kate mused aloud.

The author cocked his head, thoughtful. "You mean, that we weren't almost eaten by a tiger or drowned in the Hudson or blown up more times than I can count?" he asked with a grimace. "That our life is too ridiculous to have been real?"

"Exactly."

Castle nodded in agreement.

"I don't know if that's a good thing or if that's us somehow subconsciously living in denial," she admitted.

"Is this something Burke said?"

"No," Kate answered with a shake of her head, seeking her husband's eyes as she spoke. "But we talked a lot about denial after my shooting so I've just become more aware of it."

"Do you feel like you're living in denial?" Castle asked curiously.

"I don't think so," she replied without hesitation. "We've talked through these things. I've talked some of them over with Burke." Kate paused, gestured to their journal. "And these letters have helped because they've forced us to talk through all the things we spent so many years avoiding and denying."

"Mmmm, true," he conceded. "So in a way, we really have me to thank for our relationship."

Kate rolled her eyes with a groan.

"We do, though," she confessed, serious in her agreement. "You never gave up on us and you make me want to be a better version of myself every single day. We wouldn't have made it this far if it wasn't for you."

"And you," Castle added, unwilling to take all of the credit. "You've calmed me down, you've helped me grow and mature and find a new purpose in life."

Kate dropped her head to rest against his shoulder and he tightened his arm around her shoulders as he dipped his chin to press a kiss to the crown of her head.

"I love you," he murmured into her hair.

She nuzzled her nose into his neck, breathed him in and felt all the horrors of their past fade into the background. "I love you too."

* * *

_Thoughts?_


	4. Chapter 4

_We're all done with episode-specific chapters now, so everything from here on out will just be snapshots from their future._

* * *

**Labor Day Weekend 2016**

The moon was bright. An intense silvery glow shimmered in through the paned windows and door, echoing off the walls and casting the edges of Castle's features in an ethereal radiance. Kate trailed her eyes over the flutter of his eyelashes, the slope of his nose, the strong curve of his jaw. She was seated on the living room sofa, her back to the cushions, Castle's head on her lap and the rest of him wedged onto the length of the couch as they gazed out over the endless ocean.

Outside stars twinkled endlessly, tiny pinpricks of light dotted haphazardly across the canvas of the dark night sky. The moon's glow reflected off the ocean as well, catching the crest of each wave, riding the swell and dip as the gently churning water made its way inland.

All in all, a beautiful end to the summer. So beautiful, in fact, that Kate had no desire to head back to the city in the morning. But alas, the holiday weekend was drawing to a close and murders and paperwork awaited.

But that was on tomorrow's agenda. Tonight, she wanted nothing more than to enjoy their last night away from reality.

They'd long since emptied the bottle of red wine and their normal bedtime had come and gone as well, replaced with the gentle buzz of the alcohol and the relaxing ambiance of the night sky and the chirping birds and the soft splashes of waves against the sand that they could just barely hear through the open patio doors.

They'd brought their journal along as well, and though they hadn't yet opened it tonight seemed a perfect time to do so, to infuse the beauty of his words into the unspoiled splendor of the evening.

Their arrangement wasn't the most comfortable position for reading, nor was it entirely functional, but Castle wasn't about to move away from the fingers combing through his hair, nails scratching lightly against his scalp. And if she leaned forward and he held the book up and closed one eye so as to avoid going cross-eyed, they could make it work.

_May 18, 2016_

_Dear Kate,_

_Alexis graduates from Columbia today. I can't believe it. My little girl, all grown up._

_I still remember the day she graduated from high school as class Valedictorian. I remember, among other things, feeling so incredibly proud of her. So proud of the fact that my daughter was the one standing at the front of the room giving a speech. I've never forgotten the words she spoke that day. They rang true not just for her and her classmates, but for me and probably for everyone else in the audience. She talked about how things inevitably change, but that some things will always remain true and some people will always be our solid ground._

_At the time, I'd just walked away from you and I was angry and heartbroken and feeling so many other emotions, I don't think I was ever able to identify them all. At the time, I didn't know what was true anymore. All I could hope for was that I'd find something solid to hold onto in your absence. In retrospect, I was a fool to ever believe I could move on from you. My love for you is the truest thing I've ever known, and you will always be my solid ground._

_I can't believe four years have elapsed since that day. Time passes so fast, and I know that everyone grows up and moves on but on days like this I just want to rewind about twenty years and hold onto each moment and treasure every single minute I ever spent with Alexis. As much as I've enjoyed watching her grow and mature, I also wanted her to stay a tiny red-headed bundle of energy forever. My little girl._

_I can't even describe it. Words will never be enough to explain what it's like to watch someone grow from a helpless, crying, squirming infant into a strong, confident young adult. It's overwhelming. It's beyond the scope of anything I ever could have imagined._

_I'm so incredibly proud of her._

_In a few short months, she'll be headed off to grad school. It seems like just yesterday that she was dancing around the living room in a pink froofy tutu, and now she's dressing in pantsuits and interning at a forensic psychology office. She's making a life for herself, one that I'm no longer such an integral part of. I just can't quite wrap my head around it._

_I think your children growing up is one of those things you never completely come to grips with. That's how it's been for me, at least. I've always encouraged her to spread her wings, but that doesn't make letting go any easier._

_It's going to take some getting used to, these new aspects of her life. There have been so many changes over the past few years and I know that's always going to be the case, but that knowledge doesn't make it any easier. But when the going gets rough, I know I can count on you to lift me up. You always seem to know exactly what to say._

_Love,_

_Rick_

Kate found herself stunned by his words, unable to tear her eyes away from the page as they traced his final sentence again and again and again.

_You always seem to know exactly what to say._

That had always been him. For as long as she could remember, his words had been the thing to carry her through the hardest times, be they on the page or spilling from his lips. They'd always been there to reassure her in moments of doubt and to lift her up in moments of despair. She'd never been able to verbalize just how much his words had meant to her over the years.

Now he was saying the same about her.

Wow.

Speechless. She was absolutely speechless.

"Kate?" he prompted into the silence, the gentle curiosity in his eyes coaxing the words from the depths of her heart.

"I'm glad I can help, Castle." It was so much less than she wanted to say, but all that she could manage around the lump in her throat.

"You do," he promised. "You always do."

She smiled, blinked back the rush of emotions. "And, uh. I'm proud of you," she murmured with a smile, fingers still tangling in his hair.

He turned his head, rolling over the tops of her thighs. "Me? Shouldn't it be her you're proud of?"

"I am, Castle. I'm proud of both of you."

"Why me?"

She adjusted the bangs flopping adorably over his forehead, a failed attempt to smooth them down. "Because you raised an amazing daughter."

He chuckled. "Sometimes I think she raised herself."

She shook her head, determined to set him straight. "Even if that's true, she couldn't have done it without such a wonderful father."

The pride in his eyes was unmistakable, as was the love radiating from him as he gazed up at her. Kate thought she even saw him blink back a tear, though she wisely didn't say a word.

She wasn't a mother to Alexis. She never had been. Their relationship was an odd blend, and one that wasn't easily defined. But it worked. Nevertheless, Kate felt herself awash with pride for the girl as well, having watched her grow and mature over the last seven years.

After all, they were a family now.

Kate dipped her eyes back to the page, fixating on the emotions contained within his words – especially those about watching your child grow, mature, blossom into a young adult. Would she feel that too someday? That inexplicable love, the overwhelming sense of wonder and amazement?

She wanted to. She wanted to so badly.

From the look in his eyes, she could tell he was thinking about it too. Expanding their family.

They hadn't talked about it in months; over a year, in fact, so caught up in wedding planning, the honeymoon, enjoying their new life together. And though she wanted kids, though she knew he did as well, it was as though the long span of silence had left them both too timid to be the first to break the ice.

Kate's eyes flicked back to the journal, re-reading the words that were now playing on repeat in her mind. This notebook and the one that came before it were a testament to just how long it'd taken them to find each other, to stumble upon the same page at the same time. It was messy and fractured and so utterly miserable at times. But it was their story, and she treasured every single chapter.

Alexis was moving onto a new chapter in her life story now, and they'd done so as well with the exchange of rings a year ago. And perhaps the closing of one chapter would pave the way for the opening of another.

"I, uh…" Castle hesitated, cleared his throat. She tilted her head, found him searching her face. For encouragement or assent she wasn't sure, but the same nervous curiosity she felt was clearly reflected in his eyes, too.

Kate swallowed hard, focused on projecting a modicum of courage. "Maybe we could start trying?"

He was up from her lap in a flash, seated on the sofa next to her with one leg tucked beneath him, oriented sideways so he was facing her. "Really?"

"Yeah, I… we're not getting any younger," she pointed out. "And I think I'm ready."

"Kate…" it was half gasp, half sob as he pulled her into his arms, holding her so tightly she could scarcely breathe, but she didn't call him on it. She'd been thinking about it more and more recently, and she _did _feel ready. As ready as she imagined one could ever feel for beginning the journey of parenthood. But deep down she was terrified, and the tightness of his grip around her was the only thing keeping those feelings from bubbling to the surface and completely overwhelming her.

When he finally sat back, his smile was broad and his eyes were brimming with excitement. Despite her nervousness, his enthusiasm was infectious and she found herself grinning as well. Beneath the anxiety and fear, she _was _excited.

Castle caught her by the jaw with both hands, cradling her gently as he leaned in and melded their lips together, a soft kiss that quickly escalated into much more.

"You know," he panted as they broke for air, "we could always start now."

"I have to get my IUD removed," she reminded him.

"Well then tonight can be a practice round."

Kate raised an eyebrow, tossed him a saucy smirk. "I don't know, it seems like we've already got it down to an art form."

His hands found the hem of her shirt, fingers slipping teasingly beneath the fabric, and she couldn't suppress the shudder that rippled through her. "I'm fairly certain that, in this case, there's no such thing as too much practice."

"Is that so?"

Castle caught her lips again, deepening the kiss instantly as his hands continued their way up her back, wide and warm, spanning her skin with such tenderness. Kate rose to her knees, looped her arms around his neck and pressed herself against him. She could feel his excitement – in more ways than one – as his hands reversed their path, sliding down her back, over the curve of her ass, urging her even closer. She twined her legs around his waist as he rose to his feet, his kiss faltering at the feeling of her wrapped around him.

"You better prepare yourself," he huffed as they cleared the door to the bedroom.

"For… for what?" she managed.

He lowered her to the bed, stood to discard his t-shirt before crawling onto the bed after her. He braced himself above her, supporting his upper body as he lowered his hips, pressing her into the bed. Kate shivered in anticipation, couldn't suppress her reaction to him.

"The best practice round of your life."

* * *

_Thoughts?_


	5. Chapter 5

_There's a flashback in this chapter; the beginning and end of it are denoted by [...]_

* * *

**March 24, 2018**

It was a rainy Saturday when they next opened their journal. Outside, the streets were awash with water and the pitter patter of rain against the glass panes of their windows had grown steadily stronger. It was less of a pitter patter now and more of a roar.

Castle hadn't seen it rain this hard in a long time. Fortunately, Lily slept soundly on his lap, unmoving from when she'd fallen asleep thirty minutes ago.

Kate had taken advantage of Lily's nap time to take a quick shower and she emerged now clad in yoga pants and a hoodie, damp hair curling against her shoulders. She'd cut it three weeks back, during a much-deserved day out with Lanie while Castle stayed home with Lily. Practice – he'd claimed – for when Kate's maternity leave ran out.

She'd been back at work for a week now and he'd happily taken on the role of stay-at-home dad, but it hadn't all been smooth sailing. Kate had been wary about leaving Lily all day, and their shared fear of something happening to her on the job had been magnified tenfold since their daughter's arrival. There had been fights and disagreements and no small amount of tears.

But they'd come to a shaky truce; probably the only solution they'd ever truly reach given the dangerous and unpredictable nature of Kate's job.

Castle missed the precinct too, missed working side by side with his wife, building theory and studying the murder board while sipping coffee. He hated that he wasn't there to have her back. It had definitely been an adjustment for both of them.

But she was here now, and they had an entire weekend off; together, as a family. He knew Kate was exhausted, but he also knew she wanted to make the most of their time together.

"Hey," she murmured, tearing him from his thoughts as she sank down onto the sofa next to him.

"Hey," he greeted with a smile, one arm automatically reaching for her as she situated herself against his side, careful to avoid jostling their sleeping daughter.

Kate leaned into him, head coming to rest against his shoulder as a yawn escaped.

"Tired?"

"Always," she replied, and he grimaced in understanding. He'd forgotten how exhausting infants were. "But maybe we could read first?"

"Read?"

She gestured to the coffee table, to the spiral-bound book with the leather cover that lay at an angle near one corner, a pen neatly balanced on top. He'd been writing to her earlier, hadn't had a chance to return it to its place on his nightstand.

"Sounds perfect."

Kate shifted to retrieve the notebook, settled back into the curve of his arm as she flipped through to the next unread entry.

_Jan 3, 2017_

_Dear Kate,_

_I think you're pregnant._

She glanced up at the date, back down to his first sentence as she quickly worked through the math in her head. "You knew?" she gasped, whacking her husband across the chest and shaking her head in disbelief. But of course he did. Hadn't he always known her better than she knew herself?

He shrugged, offered a not-really-apologetic smile.

_I haven't mentioned it, because I don't want to take this experience away from you. I want to stand beside you as you work it all out in your head and I can't wait to see the look on your face when it finally falls together in your mind. So I haven't said anything._

_But I'm pretty sure I'm right._

_I can see you rolling your eyes right now. I can also hear your voice in my head asking for evidence, so here you go:_

_1\. __You threw up this morning. I know you said your stomach hasn't felt well since yesterday afternoon. And sure, it could be food poisoning. But we ate the same food yesterday, and I feel perfectly fine._

_2\. __You've been really tired. I know, I know, this last case has been rough. We were at the precinct for over fourteen hours the other day. But I've known you for almost eight years now and it's been a long time since I've seen you this sluggish._

_3\. __Despite your exhaustion, you didn't drink much of your coffee yesterday. You probably think I didn't notice, but I did. You took maybe one or two drinks, tops. And from the look on your face, it seemed as though you didn't enjoy them at all. At some point, the cup disappeared from your desk – maybe when I was in the bathroom? I'm guessing you dumped it down the drain in the break room._

_4\. __The box of tampons in our bathroom has been there for over a month now. It's almost empty. It has been since last month. It should have been replaced by now._

_Maybe it's all in my head. But we've been trying, so it's completely plausible._

_Part of me is dying to say something, but I'll continue to refrain. I hope you figure it out soon, though, because I won't be able to keep my mouth shut for long. A baby, Kate. We're going to have a baby. I can't believe it. __Our little boy or girl is going to be as intelligent and beautiful as you. I just know it. And he/she is going to be so damn lucky to have you for a mother._

_Love,_

_Rick_

"I can't believe you didn't say anything." Kate voiced in disbelief, tearing her eyes away from the page and up to her husband.

"I was going to," he admitted. "I was giving you a week, but you figured it out a couple days later."

[…]

Kate took a sick day, spent the morning and most of the afternoon alternating between their bed and the bathroom floor, and Castle felt bad leaving her alone but he had a meeting at Black Pawn that couldn't be rescheduled followed by a dentist appointment that he wouldn't necessarily mind rescheduling.

She was feeling somewhat better by the time he arrived home, so he joined her in bed and they decided to pass the time by reading a few pages of their journal. It was the third letter that triggered the realization, the letter he wrote the day after they babysat Nicholas and Sarah Grace for the first time. Castle had filled the page with his observations of her interactions with the little Ryans, his excitement for the day they started their own family, and it hit her like a ton of bricks.

When Castle finished reading and lifted his eyes to his wife she was frozen in place, eyes staring unseeing at the page.

"Kate?" he called.

No response.

Castle rested a tender hand on her forearm, tried again. "Kate?"

She turned her head in slow motion, eyes wide with shock, one hand finding purchase on his thigh. He automatically reached out to cover it with his own, the touch grounding, reassuring. Kate closed her eyes to regain her composure, took a deep breath and released it slowly. She couldn't believe she'd missed the signs, but after reading the letter it was suddenly so clear.

"Castle," she whispered, blinking her eyes open and seeking his.

He squeezed her hand, gentle encouragement as she struggled to form a complete sentence.

"I'm two weeks late. I didn't even realize, with work and the holidays…" she trailed off. "But this week with my stomach, I think…" Kate swallowed hard, rolling the words around on her tongue before forcing them out, the sentence so strange, so foreign as it spilled from her lips. "I think I'm pregnant."

The smile that spread across his face was one of the most beautiful things she'd ever seen, overtaken only by the pure love that swirled in his eyes, radiating out from the intense, clear blue. His gaze flicked from her face down to her stomach, back to her face and again down to her stomach. As though, in the midst of his excitement, he couldn't decide where to focus his attention.

Kate sat frozen, watching with a mixture of nervousness and amusement as his eyes finally settled on her stomach. His left hand reached out, palm settling warm and wide on her still-flat stomach, and she could feel the heat of his touch through the fabric of her shirt.

"We're having a baby," he whispered, the words rough, as though forced through a lump in his throat.

"I haven't taken a test yet," she reminded him.

"We're having a baby," Castle repeated in awe, paying no mind to her words. His hand slid the rest of the way across her stomach, fingers curving around her side as he tugged her to him. Kate came easily, pliable in the strong grasp of his arms as he settled back against the pillows with her draped over him.

"You're shaking," she murmured into the trembling muscles of his shoulder.

"So are you."

"Are you okay?" she asked hesitantly. They'd been talking about it, had stopped using birth control. She knew they both wanted this. And yet, irrationally, some part of her was still nervous as to his reaction.

"Okay?" He huffed a laugh. "I'm so much better than okay right now. We're having a baby, Kate!"

[…]

He still remembered the mad dash he'd made to the twenty-four-hour drug store down the street just a few minutes later. The nervous three minutes as they waited for the results of the test to show up. The elation when it was positive. She'd hugged him so tightly in that moment.

(She later admitted she was mostly clinging to him out of sheer terror.)

"I can't believe I'm saying this, but I kind of miss it," she murmured, pulling him from the treasured memory.

"Being pregnant?"

Kate nodded. "I mean, I don't miss morning sickness or having to pee every five minutes. But the rest of it was pretty amazing."

"You're amazing," he voiced sappily, and she rolled her eyes. "But you are," he continued, unrelenting. "You grew a baby inside of you, Kate. And looked absolutely gorgeous in the process, might I add."

She smiled gently, warmed by his words.

"You know," Castle mentioned in a low voice. "We could always do it again."

"Classy," Kate quipped, but she couldn't stop herself from flashing back to the way they enthusiastically _did it_ up against the wall earlier that morning while Lily was sound asleep.

"I meant a baby," he clarified with a raised eyebrow. "But I'm glad to know that's where your mind went."

"You want to have another kid?" she asked, all thoughts of up-against-the-wall sex vanishing like steam into the air.

"I just thought… we don't have to…" Castle offered awkwardly.

"No, I… it took me by surprise is all," she placated, eyes dropping to the adorable, brown-haired baby girl curled in his lap. "She's only six months old."

"It doesn't have to be right now." He reached out, traced the side of his finger over their daughter's jawline. She readjusted her arm but otherwise didn't stir. "I'm enjoying this little one at the moment."

"Me too," Kate murmured, eyes fixed on her daughter, so loving and sweet.

She still found it hard to believe at times that this was her life. She was wife to an amazing man and mother to an adorable baby girl; things she never thought she'd be.

Lily squirmed beneath Castle's touch then, big blue eyes blinking open, curiously taking in her surroundings. Kate smiled gently, reached out to lift the little girl, cradle her to her chest while Castle sat back to watch. He was so in awe of Kate, of how quickly she'd adapted to motherhood, of how raw and open and doting she was when it came to their daughter.

In all the years he'd known her, he didn't think he'd ever seen her so free.

So happy.

* * *

_Thoughts?_


	6. Chapter 6

_There are two letters in this one; credit for the second goes to Chantal. Thank you for sending me this idea, it added so much to this chapter!_

* * *

**August 25, 2018**

"Hey, didn't expect you back so early."

Kate smiled as she approached the bed, rested a hand on his thigh as she leaned in for a kiss. "Lanie got called in."

"Body?"

She hummed a reply as she pulled away. "Not our jurisdiction, though." She toed out of her sandals, leaving her barefooted against the bedroom floor. The green and white sundress softly hugged her upper body before flaring out at the hips, falling to her knees. Castle's eyes were more fixated on her chest at the moment, though, the neckline revealing, just enough to be teasing.

"Whatcha working on?" Kate questioned.

He pulled his eyes back up to her face, didn't miss her smirk. "Writing."

"Nikki?"

Castle shook his head. "Beautiful police detective. You may have heard of her. She spends her days kicking ass as one of New York's finest. And every night, she comes home to me."

Kate shook her head. "Nope, no idea who you're talking about."

"Come here," he growled, reaching for her. His hand landed firmly on her ass and he tugged her forward enthusiastically.

"So demanding," she murmured, no disapproval in her voice. She came easily, stepping up to stand right next to the bed. Castle's hand slid further around her, coming to rest on her opposite hip. She reached out to comb her fingers through his hair, smiled as he nuzzled into her stomach.

"Let me go change and then we can read, hmmm?"

He pressed a kiss to her chest through her dress, grinning into her sternum when she smiled down at him.

Kate trailed her fingers through his hair once more before stepping back, heading for the bathroom. "Be right back," she promised.

* * *

While Kate slipped into her pajamas, brushed her teeth and washed her face, Castle wrapped up the letter he'd been working on, though he'd completely lost his train of thought after Kate had flounced into their bedroom, eyes darkened and cheeks flushed from the alcohol. He could tell she wasn't drunk, far from it. But she'd been out with Lanie for the first time in months so it stood to reason that they'd enjoyed a couple of drinks while catching up.

His wife reappeared moments later, looking soft and gorgeous in shorts and an off-the-shoulder shirt. Her chestnut hair tumbled in loose waves over her shoulders, framing the stunning smile that lifted the edges of her mouth.

"Hey," she greeted shyly, faltering under the intensity of his loving gaze. For a man who made his living with words, his eyes sometimes spoke far more than entire paragraphs of his novels.

Castle smiled back broadly as she joined him in bed, scooting up against the headboard and leaning into him, shoulder to shoulder.

He flipped back a few pages, passed the book to Kate. She settled it on her bent knees and they began to read.

_September 9, 2017_

_Dear Kate,_

_I'm writing this on my phone because I don't have any paper and it can't wait. I'll copy it into our journal by hand later. Right now I just have to get the words out._

_I'm in the hospital. But it's not like last time. No one is injured or on the brink of death this time. Well actually, I'm not convinced all the bones in my hands are fully intact, but that's a minor detail. And a small price to pay for the sight before me right now._

_I'm in the hospital, sitting next to your bed, and it's taken me ten minutes to write these first few sentences because I keep getting distracted by you. You fell asleep about fifteen minutes ago, your head lolling sideways against the pillows and your arms cradling our brand new baby girl. __I've never seen anything more beautiful in my life. You're amazing, Kate. You grew a tiny human inside of you and now she's asleep in your arms, looking like a tiny version of you. It's incredible._

_I want to climb into bed with you, wrap my arms around you both. But you also look so peaceful and I don't want to disturb you._

_I'm just so in awe. There were times I never thought we'd make it to this point. I never gave up hope, but sometimes it seemed like the universe had it out for us. But we made it, and now we have a beautiful baby girl._

_I know you're nervous, you've confessed to me more than once that you're worried you won't be a good mom, but I just want to assure you again that you're going to be fantastic. You can do anything you put your mind to, and you do it so damn well. This will be no exception. I'm so incredibly lucky to have you as my wife. And little Lily Johanna is so lucky to have you for a mom._

_I love you both so much._

_Rick_

"I can't believe she's almost a year old already," Kate murmured, eyes flicking to the baby monitor on his nightstand, but the device remained quiet.

"I know."

"Everything happens so fast."

"Tell me about it," Castle commiserated. "It feels like Alexis was born about five years ago and now she's almost twenty five."

"Is it weird?" Kate asked.

"Weird?"

"Having a twenty four year old daughter and a one year old daughter?"

"Oh," he paused, giving it some thought. "When you put it like that, yes. And I think it's odd for Alexis to have a baby half-sister."

Kate hummed her agreement.

"But I don't think about it that way. You and Alexis and Lily are the best things that've ever happened to me. We're a family and my family life has always been pretty unorthodox, so I guess this is just a continuation of that tradition."

"Mmmm."

"Is it weird for you?"

"It was at first," she admitted. "Physiologically speaking, I'm not even old enough to be Alexis's mother. But you never expected me to be a stepmother and I don't think she'd have wanted that either, so that helped."

"And now?"

Kate shrugged. "Like you said; we're a family."

"Mmm, speaking of," Castle murmured.

"Speaking of…?" she prompted.

"Family," he clarified. "There's another letter from when Lily was born."

Kate flipped the page, found it dated late October. "There is?"

He was already rising from the bed as he answered, crossing to the office. "It's not in there." He returned a moment later, holding out a folded piece of yellow paper from a legal pad. "It's not actually to you. It's to Lily. But you should read it, too."

Kate took it from him tentatively, gently unfolding the creases and smoothing the page on her lap. "You're sure."

Castle settled back into bed next to her, looped an arm around her shoulders. "Of course."

_September 12, 2017_

_Dearest Lily,_

_My baby girl. You're the most precious thing I've ever seen. You're only three days old and already I love you so much. I'm having trouble putting it all into words, although some of that might be the sleep deprivation._

_You're sleeping right now, and so is your mama, so I wanted to take a moment to write you a letter before I join the two of you in your nap._

_There are so many things I want to say to you, and I'm sure I'll tell you many of them once you're older, but right now I just want to treasure every moment because I know you'll grow up way too fast. Time is funny that way. I know you don't have any concept of time right now, but you will. I know you're also too young to have much of an understanding of anything that's happening around you, but I want to take this opportunity to tell you about your family, because they all love you so very much._

_We'll start with your gram. My mother. She's the one with short red hair, brightly colored clothing, and a flare for the dramatic. Sometimes you're going to want to roll your eyes at her and sometimes she might embarrass you, but she loves you and she loves being your grandmother and she's been holding you in her arms every chance she gets. She'll be around a lot, you'll get to know her very well._

_Then there's your grandpa Jim. Your mama's father. He's much more stoic than your gram is but he loves you just as much. I've never seen him cry before, but the first time he held you in his arms, there were tears in his eyes. He's so excited to be your grandpa and to watch you grow up. Also, he has lots of embarrassing stories about your mama when she was a little girl._

Kate whacked her husband in the chest with the back of her hand, but he must have been anticipating her reaction because he easily caught her fingers with his own, twined their hands together and rested them against his thigh.

_Your other grandma isn't here anymore; she's been gone for many years now. I never even got to meet her. But I know all about her from your mama and grandpa, and as you get older we'll tell you all about her, too. She was an amazing woman and I hope the stories about her inspire you the same way they've always inspired me. The Beckett woman are pretty incredible; you have some strong, fierce, remarkable women to look up to._

Kate tightened her grip on Castle's hand, leaned her temple to rest against his.

_Next is your half-sister; Alexis. She's the one with the long red hair and the same bright blue eyes that you have. When she was a kid, she always wanted to have a younger sibling. She's a lot older than you, but she's so excited to finally be a big sister. There will probably be times when you want someone to talk to who isn't your mama or me, and I know Alexis will always be there for you when those moments arrive. Of all of us, she's almost always been the mature one; I know she'll give you good advice._

_You have some unofficial family members, too. Your Uncles Javi and Kevin and your Aunts Lanie and Jenny. They're not related to you by blood, but there's more than one kind of family. You'll learn that as you grow up. There's the family you're born into and then there's the family you find as you go through life. Uncle Javi and Uncle Kevin and Aunt Lanie and Aunt Jenny: they're the family your mama and I have been lucky enough to find. They would do anything for us, just like we would do anything for them. Now you're a part of that family, too, and they would do anything for you as well. I hope someday when you're older you find yourself part of another unofficial family as wonderful as ours is._

_Last – but certainly not least – is your mama. She's the one you were just inside of for nine months. She's the one holding you now as you sleep. She's the one with dark wavy hair and eyes that are some indescribable mixture of green and brown and are a window to her soul. There are so many emotions in her eyes and I never tire of deciphering the messages she sends me with just one glance. One day, you'll learn to read some of those messages too. For now, I can tell you that when she looks at you, her eyes are filled with pride and happiness and so much love._

_Sometimes her eyes also portray nervousness. Sometimes she's worried she won't be a good mother to you. But I know better. Your mama is the most intelligent, tenacious, compassionate, loving person I know. She's beautiful inside and out, and I know she's going to be a fantastic mother. She already is._

_No matter what ever happens, Lily, remember that you're surrounded by a wonderful family who will always be here for you. And always remember that all of us love you so very much._

_Love,_

_Daddy_

"Babe," Kate breathed, unable to blink back her tears. A few broke free, tumbling down her cheeks, and she hastily swiped them away. "This is beautiful."

"You're beautiful," he murmured, the words spilling out automatically, so naturally. "Watching you be a mother is the most beautiful thing I've ever seen."

More tears spilled over and she couldn't stop it even if she wanted to, couldn't suppress the waves of emotion that were rolling through her. She was so damn lucky to be able to call this incredible, wonderful, loving man her husband.

"I just…" she whispered, burying her tears in his shoulder. "I love you."

Castle maneuvered her into his embrace easily, his other arm rising to hold her close as her hands abandoned the letter and fisted in the front of his shirt.

He pressed his lips to the crown of her head, nuzzled into her hair. "I love you, too."

* * *

_Thoughts?_


	7. Chapter 7

**November 16, 2018**

Kate made her way into the living room, hands busy pulling her hair up into a bun as she walked. She wore yoga pants and a sweatshirt, and Castle too had dressed down into pajama pants and a long sleeved shirt.

He tossed a smile in her direction as she approached, only briefly breaking concentration as he topped off her steaming mug of hot chocolate with a heart-shaped arrangement of marshmallows.

"Here you are." He extended the cream colored mug in her direction as she stepped up beside him, and their fingers brushed as she slipped her fingers through the handle to cradle the warm porcelain against her palm.

Kate leaned in, pressed a swift kiss to his cheek. "Thanks."

Castle merely hummed in reply as he picked up a second, identical mug, in which marshmallows thoroughly coated the top of the steaming hot liquid, a few balanced on top in a second layer. He saw his wife's shoulders shake, heard her chuckle under her breath, but simply smiled proudly before placing a gentle hand on her back, guiding her to the pile of blankets and pillows built up in front of the hearth. Heat emanated from the fireplace, bathing the room in a cozy warmth. The glow of the flames cast the room a soft, golden color, the light of the flames dancing off each and every surface, reflected back at them in various colors.

Kate paused to gaze out the window at the thick layer of white coating Manhattan. Everything was muted, the sounds of the city softer, calmer tonight as people waded their way through seven inches of fresh snow. She was off shift for the next two days and they were snowed in at least for tonight, and she couldn't think of a better way to spend the evening than cuddled up in front of the fire with her husband.

She turned around just in time to see Castle settle into the mound of cushions, extending a hand for her to join him. Kate gladly obliged, settling into the space between his legs and leaning back against the solid strength of his chest. Castle looped his arms around her, breathing her in as she relaxed against him, released a sigh of contentment.

Minutes passed in silence as they sipped their hot cocoa, gazes mesmerized by the dancing of the flames and the flickering of shadows all around them. Only once her mug was emptied and she leaned over to set it aside did Castle break the silence.

"I grabbed our journal." He gestured to their left and Kate followed his movement, only now noticing the stack of items partially obscured by the edge of a blanket. "And today's crossword and a couple books. If you want, I mean," he amended.

She extended her arm, fingers reaching out to trace the spine of the book, soft tapping sounds flitting through the air as she traced over each spiral ring. "We could read," she suggested. "It's been a while."

Castle pressed his lips to her cheek, spoke in a low voice. "Sounds good to me."

_March 24, 2018_

_Dear Kate,_

_You've been back at work for a week now, and I miss you. I miss the precinct. I miss spending my days with you._

_Don't get me wrong; I love being a stay-at-home dad and I love Lily so much. I wouldn't trade it for anything. I just wish I could do both. I wish I could have my cake and eat it too, as they say._

_When I started shadowing you, I never imagined how much I'd come to love it. The fact that I was spending my days with you was a big factor, but it's more than that. It's the fact that I felt like I was doing something useful. I was helping people. I was making a difference._

_I miss that._

_I know we talked about this before you got pregnant, and I know it was always the plan for me to stay home with Lily while you went back to work, but it doesn't make me miss it any less. Maybe one day I'll be able to work by your side once again… maybe once Lily is in school. But until that day arrives, I'm so grateful to know that Ryan and Espo have your back. When it comes to keeping you safe, there's no one in the world I trust more than them._

_And even though we're no longer partners at the precinct, we're partners in life. We're partners in parenthood. After Meredith and I split up, I promised myself I'd never have another kid unless I had someone who would be by my side the entire way. For a long time, I wasn't sure I'd ever find that person._

_But I did, and there's no one else I'd rather have by my side than you._

_Love,_

_Rick_

Castle finished reading before Kate, and as he watched her eyes flit across the last few lines of text, he saw the sadness sweep over her features and a cloud of doubt descend in her eyes.

When she finally spoke, it wasn't at all the reaction he'd been expecting to his words. "I don't know how to do this, Castle."

"Do what?"

"Be a cop and a mom," she confessed. "Be by your side like you want."

"What do you mean?" he asked, shocked. "You are by my side."

"Yeah, for a few hours a day."

"Kate," he placated, though he could see his words were having little effect. "You have a job. That's life. Most parents have to go to work. But you wake up with me every morning and you come home to me every night, and that _is _what I want."

"I don't know if that's what I want," she replied, chin dipping, eyes falling closed in shame.

In that heart-stopping moment, Castle felt the dread settle in the pit of his stomach. "Are you saying you want a divorce?"

"What?" Kate gasped and recoiled from her husband, eyes wide and frantic as they sought his. "Why would you… do _you _want a divorce?"

"Of course not."

"Then why did you ask?"

"Because you said this isn't what you want."

She released a noise that fell somewhere on the spectrum between hysterical and disbelief, muffled beneath her hands as they rose to cover her mouth. "I meant work," she clarified, peeling her hands away and dropping one to her chest. "Oh my God, don't scare me like that."

"Sorry," he offered with a grimace. Castle paused, allowing their misunderstanding to be cleared from the air before speaking again. "Are you thinking about quitting?"

Financially speaking, she didn't need to work. They didn't need the money. He'd support her either way, but this was a decision she had to make on her own.

Kate averted her eyes again as her earlier sadness returned. "I don't know. I… I keep missing all the important moments. I was at a crime scene when Lily took her first steps. I was working late when she said her first words. I miss all of her firsts and those are memories I'll never have now and I just…" she trailed off, lower lip quivering and tears in her eyes. "What kind of a mother isn't there for all of the important moments?"

"Kate…"

"I just…" she uttered again, but before any more words could come out, the tears sprung free and she crumpled into him in despair. "I feel like such a failure."

"You're not," Castle promised instantly, catching her around the waist as she fell into him. She'd been back at work for eight months now, but this was the first indication she'd given that she felt this way. He wondered if he'd missed the signs, or if this was a recent development. Either way, the trembling sobs wracking his wife's body were completely breaking his heart. "You're a wonderful mother."

She scoffed – at least, he thought it was supposed to be a scoff, but it was difficult to tell with her face pressed into his chest. "I'm never around."

"You were with Lily day and night for the first six months," he reminded her, one hand rising to comb through her hair, nails lightly scratching her scalp. "And yes, you're at work for part of the day now, but you're still here in the morning when she wakes and in the evening for dinner and bath and bedtime, and when she wakes in the middle of the night. And I know you're exhausted, yet you still go above and beyond for her."

She turned to press her cheek flat against his chest, face still largely concealed by her brunette waves. "But I'm not here for the important things."

"Of course you are," Castle continued, not missing a beat. "Feeding her, holding her, comforting her… in the end, that's what's important. You show her how much you love her on a daily basis, and you have a bond with her that will last a lifetime, and together we're raising her in a secure and loving environment. And when you're not here with her, you're out in the world making a difference. You're making Manhattan a safer place for her to grow up, and when she's old enough to understand that, you'll be an incredible role model for her."

Kate finally lifted her head and blinked up at him, tears still clouding her eyes, but beneath the shimmering droplets the cloud was beginning to lift.

"I missed Alexis's first steps," Castle confessed, watching his wife's eyes widen at the realization that she wasn't alone in this. His hand fell to his lap, and he took a moment to coil his fingers with hers before continuing. "I was at a book signing and she was home with Meredith and I missed it. Believe me when I say I know how devastating it feels. But I still got to see her teetering around the house when I came home that evening… just like you did with Lily."

Kate couldn't help the smile that tugged at her lips at the memory of their little girl walking into her arms for the first time.

"And also," Castle added, one final attempt to erase the devastation from his wife's face, "this may sound harsh, but Lily won't remember these moments. But she will remember all her future school concerts and plays and dance recitals and soccer games – or whatever activities she takes part in – and I know you'll be there for all of those."

"Of course I will," she agreed.

"Then you have nothing to worry about," he assured her.

She didn't look fully convinced, but the tears had subsided and if there were any lingering doubts, she was doing a good job of concealing them. "Thanks, babe," she sniffed.

Castle tightened his arms around her, cradling her to him. Outside the snow continued to coat the city, but inside the fireplace flickered in front of them, heat from the mesmerizing flames creating a cocoon of warmth.

"That's what I'm here for," he answered easily.

* * *

_Thoughts?_


	8. Chapter 8

**January 9, 2019**

A gentle snow fell from the sky as they stepped into the cemetery, walking a familiar path to Johanna Beckett's grave. This was the fourth year in a row Kate had brought him with her on this day, and he always felt honored to be a part of this deeply important ritual.

The first year, Kate told her all about their wedding and honeymoon, smiles mingling with her tears as she relayed the memories of these special times in their lives. Castle stood silently by her side, holding her up when she needed the strength and giving her space when she needed a moment alone with her overwhelmed emotions.

The second year was all about Kate's pregnancy, which had only just been confirmed a few days earlier. For Castle, this was the most difficult moment to watch as Kate struggled to balance the joy of their impending parenthood with the devastation that Johanna wasn't there to meet her future grandchild.

Last year, January ninth had been surprisingly warm for the middle of winter, so they bundled up little four-month-old Lily and brought her to meet her grandmother for the first time.

This year, Lily was with Alexis for the morning, leaving Kate and Castle alone in the cemetery. The city was draped in a light coating of snowflakes; a few caught in Kate's eyelashes, decorated her hair as she came to a stop in front of her mother's grave and bent down to lay a fresh bunch of flowers. As she began to speak softly, Castle slipped into the background, giving her precious time alone with Johanna. She would reach for him when she was ready.

* * *

They were chilled to the bone by the time they stepped out of the cemetery and back onto the sidewalk. They didn't often use the car service for their regular day to day trips, but with the weather and the sadness it seemed appropriate today to let someone else drive while they sat side by side in the back seat.

Once they were settled in and pulling out into traffic, Castle reached into the seat back pocket and removed a small spiral bound book.

Our journal," he offered as Kate tilted her head questioningly. "The next letter is from Mother's Day and I thought… if you want."

"Okay," Kate agreed after a moment of contemplation.

Castle flipped through to the correct page and settled the book on the table formed by their adjacent thighs.

_May 13, 2018_

_Dear Kate,_

_I imagine today is incredibly bittersweet for you. I'm writing this letter to let you know I'm here for you in whatever capacity you need._

_I remember three years ago, the first time you asked me to come with you to the cemetery on this day, to lay flowers at your mother's grave. We were planning our wedding, and you told her all about it. You told her how you wished she could be there to see it and to meet me and to see how happy you were._

_I remember being so in love with you as I heard you speak those words; so in love with you that I actually started crying. I wished so badly she could be there as well. I've always wished I'd had the chance to meet her, because if she's anything like the woman you've described, I'm sure she was absolutely amazing. And I know I would have loved her._

"You would have," Kate murmured, covering his hand with hers and squeezing gently. "And she'd have loved you so much, too."

His heart twisted at her words, at the bittersweet juxtaposition of hearing her promise, believing her words and yet never knowing for sure.

_I know I've said this before, but I wish there was something I could do to take away this pain and fill this hole in your heart. I wish I could just wrap you in my arms and make it all go away. But I know it doesn't work that way. __So today, my number one goal is to make you happy. I want this day to be special, full of happy memories to balance out the sad. I want you to know how much I love you, how much I appreciate all that you do, both for me and for Lily. _

_I'm the luckiest guy in the world to call you my wife. And our daughter is so lucky to have you for a mother._

_You're amazing, Kate. So amazing._

_I love you so much._

_Happy Mother's Day._

_Rick_

"I miss her so much," Kate murmured as they finished reading, tears already falling from her eyes.

"I know you do."

"I think I've missed her even more in the last couple years," she confessed, turning in her husband's arms and burying her face in his jacket. "Ever since I got pregnant."

Castle nodded in agreement, pressed his lips to her temple. Her skin was still cold to the touch but she was warm in his arms. "Understandable."

"Don't get me wrong, your mother was great," Kate clarified. "She was so supportive, and so was my dad and everyone at work, but it wasn't the same."

"Of course not," he agreed.

"She would've been our biggest fans," she murmured, voice catching in her throat on the final syllable. "She was your biggest fan for as long as I could remember."

Castle sobered instantly, and yet he couldn't help but feel overwhelmed with pride. That his words had captured the attention of such an extraordinary woman never failed to amaze him. He already knew Johanna had read his books, that she enjoyed them, but perhaps there was more to it than that.

"Yeah?" he asked gently.

Kate smiled, lifted her head to seek his gaze. "My mom read so many books but she always said yours were her favorites."

He opened his mouth to speak but found himself at a loss for words.

"You know, she went to one of your readings once."

He shook his head in confusion. "She did?"

Kate smiled reminiscently. "Mmhmm. Dad and I teased her for days."

"When was this?"

Kate leaned back into his chest, resting her cheek against the warm fabric of his coat. "I must've been about fifteen or so. You were doing a reading and signing at some little bookstore in Midtown. She was so excited about it."

Castle shook his head. He'd done dozens of those over the years, didn't have any particular memory of this specific event.

He was struck with a sudden realization, tilted his chin to gaze at his wife. "Did I… meet her?"

Kate shook her head against his sternum. "She wanted to stay and get her book signed but she got called into work."

"I wish I could say I remembered seeing her there," he confessed.

She lifted her head, eyebrow raised. "Castle, she was one of a hundred people crowded in the audience."

"But she was your mother," he breathed. "I just wish – I wish I could've met her."

"Even if you had, you wouldn't have remembered her. Just like you don't remember meeting me."

"I know, but…" he sighed, trailed off.

"I know," Kate murmured in agreement. "But she loved your books, Castle. She's the reason I started reading them." A smile split her face despite the lingering tears. "She's the reason I crashed your book party."

Castle tightened his grip, tugging her into the cove of his body and cradling her head in his hand. He pressed a kiss to her crown, tasting the remnants of the snowflakes that dusted her hair.

"Best party-crasher ever."

* * *

_Thoughts?_


	9. Chapter 9

**July 17, 2019**

They woke to the sound of Kate's alarm.

It was an unusual occurrence; usually it was Lily who woke them. But today, their daughter was sleeping soundly and Kate was able to silence the device and roll back into her husband's arms.

The alarm sounded again five minutes later and this time it was Castle who reached for it, stretching over his wife and fumbling around for the device. Something tumbled to the floor and Kate pried her eyes open, peeked over the edge of the mattress to see a brown leather notebook splayed across the hard wood. It was open and no doubt the pages were getting bent, and if not for the fact that she treasured their journal so much, she would have left it there for later.

But instead, she leaned over and retrieved the fallen book, smoothing out the pages and gently pressing it closed.

"We could read," Castle suggested from behind her.

Kate glanced at the clock, down to the notebook in her hands; she supposed she could spare a few minutes.

_February 1, 2019_

_Dear Captain Beckett,_

_I like the sound of that. Somehow, it's even sexier than 'Detective.'_

_Seeing you in your own office, behind that large desk, in your captain clothes… I'm loving the new look, by the way. As much as I love you naked or in a bikini or wearing only lingerie, you somehow manage to make being fully clothed sexy as hell._

_Or maybe I just like it when you're in charge._

_(Not maybe. Definitely. I definitely like it when you're in charge. But you already know that.)_

"You do, huh?" Kate murmured, voice deliberately low and teasing even though her eyes never left the page.

"You know I do," he replied and, wow, when did his voice become so rough and broken? He was further gone than he thought, apparently.

She lowered her voice to match his, throaty and oh so arousing. "Is there something in particular you'd like me to be in charge of?"

Castle's hand slipped beneath the hem of her sleep shorts, palming the back of her thigh, fingers flirting with the curve of her ass. "Perhaps some… pre-work activities?" He paused, raised an eyebrow. "Can we add that to the agenda, _Captain_?"

Kate pretended to consult her schedule, pretended as though there was even the slightest chance that they _weren't_ going to start their day with mind-blowing orgasms.

"Well, Mr. Castle, I think that can be arranged," she replied thoughtfully. "Under one condition."

"And what would that be?"

The feel of cold metal closing around his left wrist was all the answer he needed.

* * *

Castle was still catching his breath when she reached up to release the cuffs, free his arms from their position over his head. Her chest was directly above his face as she leaned over him to set the cuffs on the nightstand and he pressed his lips to her sensitive skin, eliciting a shiver.

The blindfold that had initially covered his eyes was somewhere on the floor now, too, hastily tossed aside. He loved it when she tied him up, loved the heightened reactions to the touch of her hands and her lips and her tongue when he couldn't see what she was going to do next. But even after all this time, there was no way in hell he was going to miss an opportunity to watch her fall apart.

"I think it's a good thing I don't come to the precinct anymore," he panted after a long moment.

"Hmmm?" Kate settled back into the bed at his side and he wasted no time in drawing her into his arms, sweat mingling as their bare bodies came into contact.

"I wouldn't be able to keep my hands to myself."

"So you've said," she agreed, remembering the words she'd just barely had a chance to read before they got – well – sidetracked. She fumbled for the journal now, found it beneath her pillow, wedged against the headboard.

_It's always been a challenge to keep my hands to myself at work, but I'm almost certain it would be even harder now._

_(Pun intended.)_

Kate groaned, rolled her eyes. Leave it to her husband to always find the double entendre.

_Before, your desk was in the middle of the bullpen where everyone could see. Now it's in an office with a door and blinds and a sofa. Now, we could lock the door, shut the blinds, and turn out the lights. Or I could slip beneath your desk on a particularly stressful day, use my fingers and mouth to help you… de-stress. _

Kate bit her lip, pressed her legs together at the thought and promptly shuddered. Okay, so she was still a little on edge from her earlier orgasm.

_As fun as it is to fantasize about these things, though, you know I would never do anything to compromise your authority or risk your job. I've seen how hard you've worked for this promotion. I know how much your work means to you. I know your tenure as captain is temporary; it's only a matter of time before you climb even further up the ladder. I'd never do anything to jeopardize that._

_So tonight, we can celebrate your promotion in private._

_Tonight, I'll be in charge… because I know you love it when I am._

_(I do too.)_

_Tonight, I'll tell you how proud I am to call myself your husband. Tonight, I'll remind you how incredible and intelligent and fierce and determined you are. Tonight, I'll show you once again how much I love you._

_I'm proud of you, Captain Beckett._

_Love,_

_Rick_

Castle nuzzled against her shoulder as they reached the end of the page, breathing her in. His arm was still laced low across her back, fingers resting in the crook of her opposite hip. Kate could feel the cool press of his wedding ring against her skin, a stark contrast to the heat of his palm. She lifted her arm, fingers unfurling to comb through his hair, gently teasing through the soft strands, still slightly damp and askew from their early morning activities.

The silence descended, not uncomfortable or awkward, but lazy and serene as they enjoyed their last few moments cuddled in bed before they had to rise to face the day. Lily would wake any moment and Kate needed to be at work in a little over an hour.

At long last, she quietly closed the journal, fingers of her right hand slipping from his hair as she leaned forward to replace the book on her nightstand. She rose, dislodging Castle's arm from around her; the limb reluctantly fell to the bed.

Kate turned, leaned down to press a soft kiss to his lips. He smiled into the brush of her mouth, sated eyes opening languidly as she pulled away. Kate grinned back, so affectionate, so in love, the expression never falling from her face as she crossed to the master bath.

Castle craned his neck to watch her go, eyes briefly locking with hers before the door snicked shut between them. Only once the sound of water in the pipes echoed through the walls did he throw back the covers, extricate himself from the fortress of their bed. He shrugged on a bathrobe, made his way to the kitchen, retrieved two mugs from the cupboard even as the coffee maker was already hard at work.

For all the things that had changed in their first four years of married life, some things remained exactly the same. And though he got to kiss her good morning now, though they no longer needed a steaming cup of caffeine to supplement that which for so many years went unsaid, it was a part of them.

Always would be.

Only now, instead of a brilliant smile, she would lean in and drop a tender kiss to his mouth as he passed her a fresh mug of the hot liquid, her whispered thank you muffled by the press of his lips.

And every morning as she took the first sip, the caffeine suffusing her veins, she could hear his voice in her head.

_I love you._

* * *

_Thoughts?_


	10. Chapter 10

_There's a flashback again in this chapter; as before, the beginning and end are denoted by [...]_

* * *

**December 11, 2020**

She'd forgotten how exhausting pregnancy was.

With only a handful of active cases, no outstanding paperwork, and a rare lack of meetings, it had been a fairly slow day. However, Kate was finding herself more easily fatigued recently, and she was very much looking forward to a nap before dinner.

Upon arrival at the loft, Kate hung her coat, slipped off her shoes, and made her way to the sofa. Castle was there right away, arranging pillows while she tossed a blanket over her legs and settled into the cushions.

"I'll make us dinner," Castle murmured. "You get some rest."

She smiled as he leaned down to press his lips to hers. "Thanks."

After whipping up some marinara sauce and leaving it to simmer on the stove, Castle went in search of his wife. She was fast asleep on the sofa; he briefly considered waking her but opted against it, deciding instead to let her sleep. She clearly needed it. And he was happy to spend some quality time with their soon-to-be sons.

In fact, Castle decided, rising and retrieving something from their bedroom, he was going to tell them all about their amazing mother.

"Hey, little ones," he cooed upon his return, sinking onto the edge of the couch near Kate's hip, careful not to wake her. He smoothed the blanket down over her legs before opening their journal and beginning to speak in a low voice. "You guys tired Mama out. But that's okay. Your mama's a hard worker, she deserves a good long nap."

"Your mama is an amazing woman. You'll see that for yourself in a few short months. But until then, I'm going to tell you all about her." He flipped to the next page in the journal, smoothed down the paper. "Let's start with the entire series of novels she's inspired."

_September 22, 2020_

_Dear Kate,_

_I can't believe it. This day has always seemed so far away, an abstract concept off in the distance. But it's here, and I can't believe it. I don't want to believe it._

_Today, the final Nikki Heat book is being released._

_I knew it was coming. From the minute I started writing _Heat Wave, _I knew it was a story that would someday come to an end. After all, everything eventually does. But when I first created the character, I never could have imagined how much of an impact she would have on my life. How important she would become to me. __I never thought it would be this hard to let her go._

_But lucky for me, I still have you. I'll always have you._

"You should see her, babies," Castle murmured, breaking script. "She's gorgeous. Her eyes are an ever-changing sea of green and brown and everything in between, and they say more than I could ever put into words. Her smile lights up a room and her happiness is contagious. She's radiant."

He paused for a breath, fingers coming to rest on Kate's growing stomach. "But it's more than that. She's intelligent and witty and she keeps me on my toes. She's fierce and determined, which is why she's so good at her job. But she's also the most kind and compassionate person I've ever met. She's amazing. And she's going to love you two so much."

Castle felt Kate stir and leaned down to press a kiss to her stomach before lifting his head, eyes seeking hers. He wasn't sure how long she'd been awake, but from the blissful smile on her face and the love radiating from her eyes, she'd heard at least some of his words.

Kate allowed her eyes to slip closed once more and Castle turned his attention back to the remainder of the letter, continued to read aloud to their unborn twins.

_Even though I'm no longer writing Nikki, I know I'll continue to be inspired by you on a daily basis. And who knows, maybe Nikki and Rook's future kids will grow up to be kick ass law enforcement officials who can each star in a series of their own._

Kate whacked him in the side at that, and he glanced up sheepishly just in time to see her roll her eyes.

"What?" Castle defended innocently.

She shook her head, but the twinkle in her gaze said all he needed to know.

_It was bittersweet, writing the ending. I'm proud of their story, of how it all unfolded. I have no doubt that this was a solid place to end, one that feels organic to their characters. It was the right time. But that doesn't make it any easier to let go._

_Regardless, know that Nikki will always hold a special place in my heart._

_Just like you._

_Love,_

_Rick_

Kate closed her eyes again, leaned her head back against the pillow as memories of the book launch party flitted through her mind. It was an emotional but lovely night, and one that would stay with her forever.

[…]

The limo pulled up outside the building, coming to a stop alongside a plethora of cameras and reporters. It was the first time in months that Kate had stepped out publicly with Castle, and their first appearance since learning she was pregnant again. She was only eight weeks along, wasn't showing yet, so for now it would remain a secret from the world.

"You ready for this?" came Castle's voice, soft and low.

She took a deep breath, released it slowly. She could do this. "Yeah."

Castle's hand slipped from hers then and he smoothly exited the limo, crossing around to open her door for her, guide her out of the car. Questions were already coming at them from all directions, camera flashes blinding as they stepped up onto the sidewalk. But with Kate's arm firmly twined with his, Castle heard none of it, eyes focused solely on his wife, her knee-length black dress, her elegant heels, the way her hair fell around her face, beautifully framing her darkly-lined eyes. He could feel the nervousness thrumming through her, but on the outside she appeared composed, perfectly poised and unbelievably stunning.

Ignoring the melee of the press, they made their way into the building side by side, stopping only once they were inside. Castle looped an arm low around Kate's back, the sides of their heads leaning together as they paused to pose for a few photos.

After that, it was the normal assortment of cacophony; interviews to be given, hands to shake, champagne to sip – or avoid, in her case, and hope no one noticed she was drinking water instead. While Castle made his rounds, Kate caught up with Lanie, Esposito, Ryan, and Jenny, the conversation a welcome distraction from the noise and the nosy reporters and everyone else who seemed determined to strike up a conversation with her.

Thankfully, Castle returned to her side as soon as possible, leaning in to press a kiss to her cheek as he sidled up next to her. Ryan and Esposito greeted him with a hand shake and a half-hug, Lanie and Jenny smiling and offering their congratulations. They group fell into an easy conversation then, full of smiles and laughs and good-natured ribbing.

But the moment they fell into a natural lull, Castle was slipping his arm around her waist, leaning in to murmur into her ear, voice low enough for only her to hear. "There's something you need to see."

Butterflies were beating a steady rhythm in her stomach as he led her to the center of the room, stopping by the freshly revealed shelves of novels, dozens of copies of _Heat Everlasting_ on display. The cover was a deep purple with two silhouetted figures on the front, walking hand in hand into the distance. Kate hadn't yet read the book, knew very little about the storyline; if the cover was any indication, Nikki and Rook were slated for a happy ending.

And he'd been remarkably tight-lipped about the dedication as well, making her promise not to read it until he was there with her.

With slightly shaky hands, Kate reached out and lifted one of the copies. A thrill raced through her as she traced a finger down the spine, hooked a finger over the edge of the cover. The noise in the room faded away as people became aware of the scene unfolding, party attendees holding their breaths in unison as Kate peeled back the cover.

Her breath caught as she read his words, tears already filling her eyes, and she'd promised herself she wouldn't cry in public but damn him, the tears were already falling. Kate turned in his grasp, one hand cradling the book to her chest, the other rising to cup his jaw, pull him in for a deep kiss.

"I love you," she murmured against him, pressed her lips to his once more.

[…]

"Kate?"

She jerked back into awareness. "Hmmm?"

"You okay?"

She nodded, smiled gently. "Just remembering."

"The launch party?"

"Mmm, that," she conceded. "And the dedication."

"Black Pawn thought it was too much," Castle admitted.

"Really?"

"I told them it was non-negotiable."

"It was perfect, Babe."

He tilted his head, eyes meeting hers in a slightly insecure gaze. "Yeah?"

She leaned into his side, hand coming to rest on his chest, gently stroking the soft fabric of his shirt. "Yeah."

* * *

_To Kate. Thank you for crashing my book party eleven years ago. My life has been forever changed by that moment and is forever enriched by your presence. I love you._

* * *

_Thoughts?_


	11. Chapter 11

**March 30, 2021**

"Hey, you feeling better?"

"Mmmm," Kate moaned unconvincingly. "A bit."

Castle sank onto the bed beside her, hand coming to rest on her thigh beneath her distended stomach. She was on week two of bedrest and he knew she was going stir crazy. He'd been swinging by the precinct periodically to pick up paperwork so she could manage at least that portion of her job from home, but he knew she missed actually being at work.

The bedrest had been hard on Lily, too, always a bundle of energy wanting to run and bounce and play with her mom; it broke Kate's heart every time she had to tell her no, offer to do something calm and quiet instead.

"I have to get going," he murmured. "Meeting starts in half an hour."

She nodded against the pillows.

"You sure you're okay?"

"I'll be fine," she promised weakly.

"Okay."

Castle stood, pausing to carefully tuck her hair behind her ear and press a soft kiss to her forehead.

"See you later."

* * *

"Hey, how're you feeling?"

Kate smiled wanly, easing back into bed and settling against the headboard. One twin was currently kicking the outside of her stomach, but the other had been playing hacky sack with her bladder for most of the afternoon, forcing several trips to the bathroom.

They were due in seven weeks, though the doctor had warned her she likely wouldn't carry them to term; as much as she wanted to prove the doctor wrong, she was in a state of perpetual discomfort and extremely ready for the pregnancy to be over.

"Better," she answered, making herself as comfortable as possible given the swollen state of her stomach. "How was your meeting?"

He shrugged, slipping out of his pants and button-down. "Just hacking out some details for the new book."

"Mmmm," she paused. "How's Lily?"

"Down for a nap, at least for a little while." Clad in pajamas now, he sank onto the bed next to his wife. "Do you need anything? Tea? Some food?"

She shook her head, extended a hand. "Just you."

He smiled, shifted until his side was pressed against hers, shoulder to shoulder against the pillows. "Better?"

Kate leaned into him, relaxed against her husband. "Much."

"Want to read a bit from our journal?" Castle suggested after a few silent moments.

She smiled to herself, still in awe of the way he always seemed to know exactly what she needed. "Sure."

Castle leaned over to retrieve the spiral-bound notebook from the nightstand, passed it to her. She flipped through to the next page, settled the journal on her ever-growing stomach, and together they began to read.

_October 1, 2020_

_Dear Kate,_

_Twins? We're having twins? I'm equal parts thrilled and terrified._

_Actually, that's a lie. I'm largely terrified. I'm almost fifty-two, and I know I'm in decent shape but I'm still starting to feel my age. Babies are exhausting, but I was far more fatigued with Lily than I ever was with Alexis. I can't even imagine how I'm going to be able to keep up with twins._

_Don't get me wrong; I'm excited for us and I'm so grateful we're having the opportunity to expand our family. Especially after how much trouble we had getting pregnant. Watching you be a mother is one of the most amazing things I've ever witnessed and seeing how you love Lily makes me love you even more than I ever thought possible. Watching you love our twins is going to be so beautiful._

_But deep down, I'm afraid. I'm afraid I won't be able to keep up with them. I'm afraid I won't be able to be a good father to them. I'm afraid I won't be able to pull my weight and support you the way I should. And I'm afraid that might change the way you feel about me._

"Rick," she murmured, so soft and gentle. "You're a wonderful father. Please don't ever doubt that."

"But I…"

"And the fact that you're so worried because you care so much... that does change the way I feel about you," she confessed. "It makes me love you even more."

"What about when I can't keep up?"

"Remember all the times I was nervous about motherhood when I was pregnant with Lily?" she questioned. "Remember how I was afraid that I'd mess up and you'd think less of me?"

"I could never think less of you," he answered immediately.

Kate raised an eyebrow, pursed her lips but didn't say a word.

"Right," he mumbled, falling silent, eventually allowing his eyes to fall back to the journal.

_I know you were the nervous one when we were pregnant with Lily, but you're an amazing mother. You deserve a husband who is able to pull his weight, and our kids deserve a father who can give them everything. I'm terrified I won't be able to be that person._

_I feel like I owe you an apology in advance._

"You don't," Kate assured him, her words so certain. "I know you. You're going to give it everything you have, and you have nothing to be sorry for."

"What if everything I have isn't enough?"

"Babe, we just went through this."

He huffed a sigh. "Look me in the eye and tell me you're not even the slightest bit concerned about this."

"I'm not," she answered firmly, no doubt, no hesitation, eyes locked with his. "Now come on. Let's finish reading so we can put these thoughts away for good."

_I'm trying, Kate. I really am. I'm trying to be good for you. I'm trying to make sure you have everything you need and that you're not overworked. I know you're exhausted already, and you're only 9 weeks along. I promise to keep trying, all through your pregnancy and once the twins are born. I just hope that's enough._

_The last thing I ever want to do is let you down._

_I love you so much, and I promise to continue to give you everything I have, even if it's not enough._

_Love,_

_Rick_

"Castle?"

He lifted his eyes from the page to meet hers. "Hmmm?"

"You, this, our life," Kate enumerated, "it's everything I've ever wanted and more. It will always be more than enough."

* * *

_Thoughts?_


	12. Chapter 12

_Thank you all for your continued support and lovely reviews!_

* * *

**January 19, 2022**

"Everything okay?"

Castle jerked his head up in surprise. "Yeah, uh, hey. Lily's in bed?"

Kate nodded. "Reece too but this one wasn't sleepy." She bounced Jake in her arms as she spoke, smiled as he babbled up at her, tiny fingers playing with her ear. She'd taken to keeping her hair pulled up most of the time, ever since both Jake and Reece had decided that tugging on it was their favorite activity.

She wasn't necessarily sure that fingers in her ear was much better.

When Castle didn't reply, Kate crossed the room, rested a hip against the edge of his desk and set the baby monitor on the corner of the mahogany surface. "Rick? You sure you're okay?"

He sighed heavily, debated for a long moment before finally speaking. "I was writing. To you. I wanted to talk to you but I didn't know how to bring it up and… maybe you should just read what I have so far."

"I…" Kate hesitated. "Should I be worried?"

"No," he answered. "At least, I don't think so."

"Babe, you're scaring me."

Castle slid the journal across the wooden surface, stood and extended his arms to relieve her of Jake. At eight months, he was nearing eighteen pounds; not excessively heavy, per se, but with two seventeen-and-a-half pound babies, their arms were getting quite the workout these days.

Kate sank into the desk chair as her husband resituated Jake against his chest, already making his way out of the office cooing softly to their younger son. Reece was only twenty one minutes older but she already knew he'd be exploiting that fact all too soon, lording it over his brother whenever possible. They were growing so fast.

She followed her husband and son with her eyes until they disappeared from her sight before reaching for the journal, flipping to the entry dated today.

_Dear Kate,_

_I'm worried about us. For the first time in our ten years together, I'm feeling like the spark is gone._

_I'm sure part of it is the exhaustion; we do have three kids under the age of four, after all. Neither of us has had a good night's sleep since who knows when, and whenever we do manage a few minutes alone together we're both too tired to do much of anything. I've lost count of how many days have passed since we last had sex but it must be close to three months._

_I know sex isn't all that matters in a relationship, but I think in this case it's a contributing factor. I think we've gotten too used to not having that intimacy. I think it's becoming a new normal for us, and that scares me._

_Gina and I didn't have sex for six months prior to our divorce. Granted, we had a million other problems that caused us to split up. And even though I know it's irrational, I can't help but worry that you and I are headed down the same path._

_But there's an important difference here. With Gina, I wasn't interested in solving our problems. It didn't seem worth it and the divorce was actually somewhat of a relief. With you, it's absolutely worth it. When I married you, it was because I wanted to spend the rest of my life with you, and I'll do whatever it takes to ensure that we have our forever. I'm willing to put in the work, I'm willing to fight for you, I'm willing to do whatever it takes to bring back that spark and keep our relationship alive._

_I've been stewing over this for a few days now and I'm still not entirely sure how to broach the subject with you, but writing everything out here has helped. __Until I find the exact words and the courage to have this conversation with you, please know that I love you even more today than I did when I married you. I want everything with you: a life, a family, all the triumphs and challenges that get thrown our way. Everything._

_I want you._

_I've been physically attracted to you since the day we met and that hasn't ever changed. I know that spark is still here somewhere. It might be subdued at the moment, but it's here. We just need to stoke the flames, get them burning again. I'm certain that once we do, they'll burn brighter than ever. After all, the physical aspect of our relationship has always been easy._

_Maybe because of that, we've been neglecting it. Maybe we haven't been giving it the care and attention it deserves. Maybe the solution really is that easy. But if it's not, we'll figure it out. At the very least, this gives us a place to start._

"Is it me?" Kate blurted the moment Castle reappeared in the office sans Jake. She'd heard him murmuring softly through the baby monitor, knew both sons were fast asleep at least for the time being. They'd begun to sleep through the night a few weeks prior but one or both of them still occasionally woke in the wee hours of the morning.

"What?"

She self-consciously rested a hand over her stomach. "Is it because of me? I know I'm still a few pounds heavier tha..."

"God, Kate, no," he interrupted, crossing the room in long, determined strides and crouching down next to the desk chair. "You will always be beautiful in my eyes, please don't ever doubt that."

"I don't feel beautiful."

The words were barely more than a whisper but Castle heard them clearly; she could tell from the stricken look painting his face.

"Is it… have I been taking you for granted, because that's not…"

"No." It was her turn to cut him off this time. "It's not you. I just don't feel sexy anymore."

Her eyes fell closed around her confession, chin dipping in shame.

"Why not?"

She shook her head, didn't answer right away.

"I'm always exhausted," she finally admitted, the words murmured softly into the silence. "There are bags under my eyes that no amount of makeup can cover. My boobs are saggy, I'm covered in stretch marks," she paused to pinch the skin of her stomach that was spilling over her waistband, the few extra pregnancy pounds she hadn't yet shed, "and I have all of this."

"That's not what I see," Castle assured her, and the surprise of his words was enough to draw her eyes up to his. "I see the woman who's been juggling work and raising our three kids like a badass. I see a body that's grown and nourished our beautiful twins, which is something to be proud of. The fact that you and your body have been able to do all of that is remarkable."

Castle tugged gently on her knees, turning the chair until she was facing him and he could rest his hands on her thighs, squeezing gently. "Our bodies are going to change as we get older. Mine definitely has. But no matter what happens, I will never not find you sexy."

It was a long moment before his words had the desired effect, but slowly her lips curved up at the corners and the sadness began to lift from her eyes. "Thanks, babe."

He rose from his squatting position, pressed his lips to hers in a firm kiss he hoped would erase all of her doubts. He wasn't naïve enough to believe one kiss would be enough to solve the issue… but he did have an idea of what might.

* * *

Three days and a few phone calls later, Lily was off to spend the weekend with Grandpa Jim and Lanie was dragging Kate out for a morning of dress shopping and a mani/pedi followed by an afternoon of makeup and hairstyling in the upstairs bathroom.

Alexis showed up promptly at five p.m., having readily agreed to team up with Lanie for babysitting duty. It would be the twins' first night away from home but both Alexis and Lanie had assured the nervous parents multiple times that they had things under control.

"You guys deserve a night out, Dad," his eldest daughter promised as he strapped Jake into the double stroller next to Reece. She'd taken the boys upstairs one at a time so Kate could say goodbye, couldn't wait to see her dad's reaction when his wife finally appeared. "Go have fun. We've got this."

As if on cue, the ME appeared just then with Kate on her heels. Kate wearing a black dress and matching pumps, hair tumbling over her shoulders in ringlet curls and smoky eyes bright but struggling to conceal hints of self-consciousness and nerves.

"Kate," Castle breathed, the air whooshing from his lungs at the stunning sight before him. She gracefully descended the last few stairs and he met her at the bottom, not even bothering to hide the path of his gaze as it trailed heatedly up and down her body. "You look incredible."

"We should go," Lanie murmured, lifting the diaper bag onto her shoulder while Alexis began to maneuver the stroller through the front door.

"Definitely," Alexis agreed as they silently slipped out of the loft.

The ME tossed a glance over her shoulder as they quietly pulled the door shut; Castle's hands had already migrated to Kate's ass and hers were clinging to his neck, lips entangled in a passionate kiss. Lanie was pretty sure Kate's dress was about to end up on the floor, an afternoon of mascara and curling irons all for naught.

* * *

They didn't make their dinner reservation.

They didn't even make it out of the loft.

* * *

It was a couple days before Castle opened their notebook again, poised to tear out the partially written letter and throw it away. He grasped the edge of the page, hesitated. It wasn't right. He couldn't just remove this piece of their story.

After a lengthy debate with himself, he eventually settled for leaving it unfinished. He flipped the page and put pen to paper, allowing the words to flow into a follow-up journal entry.

_Holy hell, Kate._

_I think we can safely say we found our spark again, and the flames of desire are back with a vengeance. I've lost count of the cumulative orgasm total from the last 48 hours, but I think it's somewhere around fourteen. My legs and my ass are sore and I can see you're struggling to walk normally, too._

_I'm so sorry for losing faith in us. I'm sorry for neglecting our physical relationship. I'm sorry for not realizing sooner that you were struggling with your body image. I'm sorry if I ever said or did anything that made you feel anything less than incredibly sexy and indescribably beautiful. __I promise to never let another day pass without reminding you how incredible and intelligent and gorgeous and alluring you are._

_I love you so much._

_Rick_

* * *

_Thoughts?_


	13. Chapter 13

**September 6, 2022**

She was crying.

Kate was actually crying as she hugged Lily outside the classroom on her first day of kindergarten.

Their daughter, of course, was completely fine. She was excited for the playground, excited for new friends, already chattering happily about all the new things she'd get to learn. Their daughter had definitely inherited Castle's penchant for talking, his optimism, and his pure enthusiasm for all aspects of life.

She'd also inherited Kate's tenacity and stubbornness, but those qualities were nowhere to be found today. For now. Kate was sure they'd be hearing from Lily's teacher at some point. Their daughter could be extremely persistent.

So while Kate attempted to summon every ounce of said tenacity and stubbornness in an effort to keep her tears at bay, Castle swung their daughter up into his arms, laughing as she squealed happily. Her tiny purple backpack hung from her shoulders and her adorable unicorn dress swirled around her knees as Castle pressed a kiss to her cheek before lowering her back to the ground.

"Bye, Daddy!" Lily exclaimed with a grin, an adorable gap where one of her front lower teeth was missing. It had fallen out about a week earlier and, much to her delight, she'd received her first ever visit from the Tooth Fairy. Naturally, Castle made sure the Tooth Fairy left her $10 and a gift certificate for a celebratory ice cream cone.

Lily turned to her brothers, miraculously quiet in their stroller. "Bye Jake, bye Weece."

Both boys babbled something that resembled "Wiwy bye-bye." Stringing two words together was their most recent accomplishment, but Kate had a feeling it would be a while before they managed to properly enunciate their sister's name.

With one final wave Lily turned and skipped through the door to her classroom, leaving behind a perfectly calm Castle, happily babbling twin brothers, and a crying Kate.

* * *

By the time she showed up at work, Kate had herself under control enough to at least project a modicum of calm professionalism. But the tears were still threatening to fall and her heart was beating a nervous rhythm in her chest.

It was just school. She didn't understand her irrational reaction. Lily would be going to school daily for most of the year for the next thirteen years. This wasn't an unexpected change. This was their new normal.

She'd never imagined she'd have so much trouble adjusting to it.

* * *

By mid-morning, Kate was wrapped up in paperwork and a conference call, so when her husband showed up at her office door with two cups of coffee, she was caught completely by surprise.

"Hey," she greeted with a smile, furrowing her brow in confusion at the lack of stroller and twins. "What're you doing here?"

He shrugged with a gentle smile, sank into the sofa. "Figured I'd give the boys a chance to hang out with their uncles while I kept you company for a few minutes."

Kate crossed her arms, narrowed her eyes. "Is this because of this morning?"

"What do you mean?" They'd been married far too long for her to not recognize his false innocence face, and she narrowed her eyes more severely. "Maybe I wanted to make sure you were doing okay," he hedged.

"I'm fine," Kate insisted. It wasn't a lie. She'd been wrapped up in work, all thoughts of Lily at school pushed completely aside.

Castle looked skeptical but wisely didn't speak.

"How are you so calm about all of this?" she asked after a moment, gesturing aimlessly with both arms. "I seem to recall something about you hiding in the playground equipment on Alexis's first day of kindergarten."

"It was preschool and I hid in the bushes," he corrected, as though the details made any difference.

"Whatever," she dismissed. "My point is, why aren't you doing that today?"

He shrugged. "I guess it's easier the second time around. I already know what to expect." Castle extended one of the coffee cups, made a sideways motion with his head. "Come sit for a few minutes."

Kate came willingly, sinking into the cushions next to her husband and taking the beverage from him, relishing the caffeinated warmth as the first drink slid down her throat.

"I also brought this," he offered after a moment, producing their journal from the pocket of his jacket. "I wrote to you this morning... if you want. Or we can read it later."

"Now is good," she murmured, dropping her head to his shoulder as he thumbed through for the correct page.

_Dear Kate,_

_Our little girl is a kindergartener. I'm not sure how that's possible, because I swear it was just a few months ago that I was sitting by your hospital bed watching you hold her for the very first time. She's growing up so fast._

_I almost wish we'd decided to hold her back a year; she doesn't even turn five for another three days. But I know we made the right decision by letting her go. She's smart and mature and she's ready. I know she's going to be fine, and it would be wrong to hold her back just because I'm not ready._

_I just want to stop time and keep everything exactly the way it is right now. Or, I guess, exactly the way it was yesterday, before she went to her first day of school. I'm not ready for her to keep growing, I'm not ready for the twins to join her in school in a couple years. I'm not ready for them to grow up. It all just happens way too fast._

_And then there's us. We've been together for ten years now. I can't even believe that. It doesn't seem like it's been that long. And yet, it also seems like it's been so much longer than that. If not for my memories of Alexis as a kid, it would be so easy for me to believe that I'd been in love with you my entire adult life. _

_I've learned a lot about you in the last ten years. I've learned your history, your strengths and weaknesses, your hopes and fears. I've seen how badass you are, and yet I've also witnessed how soft and open and loving you are. I've seen it all… or so I thought._

_I never thought I'd see you cry your eyes out on our daughter's first day of school._

_I'm not making fun of you. I've been there too._

_I know you're probably feeling embarrassed, and I'm certain you're putting on a brave face at work and pretending everything is fine, but I want you to know that you have nothing to be embarrassed about. Your reaction was completely normal. Half the kindergarten parents had tears in their eyes._

_But she'll be home in a few hours, and so will you, and we'll sit down for dinner as a family like always._

_If there's one thing I've learned from working with you, it's that things change. Things always change, and in ways we could never possibly imagine. But some things also stay the same. I love you. I love Lily. And even though she's growing up and fully embracing her stubbornness and sometimes calls you a 'poopy head', Lily loves you, too. Those are things that will never change, and as long as we remember that, I know we'll be okay._

_Lily and I will see you tonight._

_Love,_

_Rick_

"I still can't believe she's in kindergarten," Castle mused as they reached the end of the letter.

"Mmmm," Kate acknowledged, glancing out into the bullpen where Ryan was somehow managing to corral both twins simultaneously while Esposito looked on with amusement. Jake and Reece were an endless stream of energy; Kate and Castle's new normal was a state of exhaustion after spending their days trying to keep up with their precocious little boys.

"And Alexis is getting married," the author said with a shake of his head. "I just…" he trailed off, utterly at a loss for words.

"Cam is a good guy," Kate murmured supportively, turning her focus back to her husband. She knew Castle was still coming to grips with Alexis's recent engagement, knew he was struggling with the fact that she was moving on to this new phase of her life.

"You really think so?"

Cameron Evans was a forensic sociologist whom Alexis had met just over a year and a half ago while completing an internship. Castle's daughter was currently nearing the end of the fifth and final year of her graduate psychology program at the John Jay College of Criminal Justice. She'd be defending her dissertation and graduating in a few months, and Castle had never been more proud of the young woman she'd become.

He and Kate knew Cam well by this point, and he was certainly a big step up from anyone his daughter had brought home in recent years. He was intelligent, polite, and very hard-working. Castle liked him. But at the same time, he didn't like him. Probably because Cam had clearly stolen the heart of his oldest daughter.

"I do," Kate murmured, her voice drawing him back. "He respects Alexis and he loves her and he's very supportive of her."

"I know," he practically whined. "But she's my little girl."

"She's grown up," Kate said matter-of-factly.

He sighed heavily, the sentiment pained. "I know. I just…" he ran both hands over his face in agitation. "I've never been good at letting go."

She patted him on the shoulder. "No, you haven't."

But without his tenacity, his unwillingness to back down, they probably wouldn't be together; even when she'd been willing to walk away, even when _he_ had, he'd never truly been able to let her go.

The ringing of Kate's phone drew them back to reality. It was a Tuesday, and while Kate appreciated that her husband had stopped by with their boys and their journal, she did need to get back to work.

* * *

Castle slipped from her office while she answered the phone, found Jake and Reece now passed out on the sofa in the break room. Ryan sat at the high top table sipping coffee and no doubt taking a moment to recover from the rambunctiousness.

"Thanks," Castle offered, taking a seat opposite Ryan.

Ryan shrugged, a silent 'don't mention it.' "How's she doing?" he asked with a head tilt in the direction of Kate's office.

"Better," Castle answered truthfully.

"You know, I ran a background check on Sarah Grace's kindergarten teacher," Ryan admitted. "Beckett yelled at me when she found out, but I think she's been an inch away from doing the same thing this morning."

Castle grinned. "How are the kids?"

"Growing so fast," Ryan lamented with a shake of his head. "Sarah Grace started third grade today and Nick is in first."

"And Jenny?"

"Still teaching second grade," he offered with a proud smile. "All the kids love her. Hey, you guys should come over for dinner soon," Ryan proposed, excitedly changing the subject. "Nick was asking about Lily the other day, and I know Sarah Grace loves to chase those two around the house," Ryan thumbed over his shoulder to the twins, still sprawled across the sofa, half asleep, "I'm sure she'd gladly wear them out for you."

"Let's do it," Castle agreed easily.

The conversation shifted then to the twisty, dramatic details of their current case, interrupted only when Jake stirred and blinked his eyes open. "Dada?"

"Hey, buddy," he whispered, rising and quietly crossing the room in response to Jake's extended hands, swooping him up into his arms.

Jake caught sight of Ryan, waved over his dad's shoulder. "Unkey." Ryan grinned.

"Did you guys have fun with Uncle Kevin?" Castle murmured.

Jake nodded eagerly, babbling a nonsensical answer.

"I think you guys wore him out," Castle continued. "So much energy."

Jake giggled, though probably because Ryan was currently doubled over, choking on his coffee.

"Siwwy," he offered.

"Well, let's make sure he's okay first," Castle told his son. "Then we can laugh."

"I'm good," Ryan gasped between coughing fits, holding up one hand into the 'okay' sign. "Just went down the wrong way."

"Da?" came Reece's voice from behind them.

"Hey, buddy," Castle greeted, squatting with some difficulty to retrieve his other son from the sofa.

They were growing so fast and were rapidly approaching the point where he wasn't going to be able to hold both of them at the same time anymore. But for now he wanted to savor these moments, even if they made his knees crackle and pop and his arms and shoulders ache.

Kate was right.

Everything was changing way too fast.

* * *

_Thoughts?_


	14. Chapter 14

**July 28, 2024**

"It's such a beautiful evening," Kate murmured, leaning back against her husband's chest, wine glass cradled against her sternum.

Castle caught her around the waist with his left arm, nose nuzzled into her neck and his own wine glass balanced in his right hand as he hummed in agreement.

July in New York was usually hot and muggy, almost intolerable at times. But tonight was a rare Sunday evening, the remnants of sunlight lingering and a soft breeze pushing the humidity out to sea. Lily, Jake, and Reece were in bed, and Castle and Kate were enjoying a blissful moment of solitude out on the roof of the loft.

A few years ago, Castle had converted much of the space into a fort for the kids. A couple waterproof picnic blankets were draped from one side to the other. There was a patio table and five chairs, numerous toys that had made their way up here, and Castle had also strung up some strands of lights. The lights currently twinkled above them as they snuggled into each other, seated on a cushioned lounge chair with the sights and sounds of the city far below.

So much had changed since they last sat up here together, just the two of them, and the biggest change of all was the topic of the letter staring up at them from the pages of their journal.

_May 26, 2024_

_Dear Kate,_

_Married. Alexis is married._

_Yesterday, I walked her down the aisle. Yesterday, she began the rest of her life with Cam._

_I know she's not my little girl any longer. She's 30. But in my mind she's still my little girl, and reality is making it more and more difficult to hang onto that illusion. Watching her grow up and complete her degrees and find a career and fall in love has been the adventure of a lifetime; I'm constantly torn between being so proud of who she's become and wanting everything to rewind and go back to a time when she was just a tiny redheaded bundle of energy who was far too young to have a PhD and a job and a husband._

_I like Cam. I do. I remember I initially expressed my doubts, but you were right. He's a good guy, and he's good for Alexis. All I can ever ask for is that my daughter is happy, and she is. I can see how happy she is when she's with him. It's just difficult to accept that I'm not her go-to guy anymore._

_I was drowning in far too many emotions yesterday to even interpret them all, and I certainly didn't remember all the things I wanted to say to you, so I'm writing them here instead. Mostly, I want to thank you. For a multiple things. First, for keeping me calm these last few days. I know when you read this you'll laugh because, objectively speaking, I haven't exactly been calm. But I've been calmer than I could have been._

True to form, Kate chuckled at his words. Leading up to the wedding he'd been quite possibly the most frazzled she'd ever seen him, but she'd found in oddly endearing.

_The second thing I want to thank you for is for being such a wonderful example for Alexis over the years. When she was younger I know she looked up to you, and I can't imagine anyone who could set a better example for my daughter. I know there have also been times she's come to you and not me for advice, and while that's been difficult for me to accept, I'm glad she has you. There's no one in the world I trust more than you to fulfill that role for her._

_As she's gotten older, I think she's looked up to both of us, especially when it came to marriage. The entire world knows I wasn't historically a prime example when it came to relationships, and part of me always worried what kind of example I was setting for Alexis. But you and I… we're solid. We're permanent. We're exactly what a relationship, a marriage, should be, and I'm glad she finally had a chance to see that. I'm glad I could finally be a good example for her_

_Lastly, thank you for everything you've done for Alexis and for me. Thank you for helping her with wedding planning and going dress shopping with her. Thank you for taking care of the kids while I danced with her yesterday, and for talking down a dramatically sobbing Meredith before she could cause any more of a disruption. Thank you for ensuring that the wedding went off without a hitch._

_I know things were rocky between you and Alexis for a time, but we're a family now. A family that just gained a new member. I remember once, during the early years of our partnership, you told me that girls who adore their fathers usually end up marrying someone just like them. I'm not sure if you were being honest or enjoying the chance to torment me, or if you even remember saying that, but it really did worry me. As much fun as I've had over the years, as much chaos as I've caused… it was fun at the time but, in retrospect, much of my life was a series of poor decisions and I'd never want Alexis – or any of our kids – to end up with someone like me. I was wild and irresponsible and pretty terrible when it came to relationships._

_For the most part, I needn't have worried. I may have consistently fought to accept the fact that my daughter had a boyfriend, but I was relieved when the first guy she was ever serious with seemed to be the opposite of me in many ways. And I'm glad that Cam is the man she's chosen to marry. He's everything a parent could want in a son-in-law, and he's nothing like I was at that age, which is a tremendous relief._

"You know," Kate interrupted their reading and turned to face him, "he is like you in some ways."

Castle whipped his head up, fixed her with wide eyes. "What?"

"Relax, Babe, I mean that as a compliment," she murmured, cupping his cheek with her palm before dropping her hand and counting off on her fingers as she spoke. "I didn't know you when you were his age, but I see a lot of similarities between the two of you. He's goofy when he's around Alexis, but he's also serious and responsible when he needs to be, just like you always were around Alexis. He's smart, he's well read, he's kind," she continued. "You don't give yourself enough credit. A few questionable decisions don't define who you are as a person."

Castle gaped at his wife, opened his mouth to speak a few times before giving up on his attempts to find words and dropping his attention back to their journal. Kate mimicked him, settling back against his chest and reading through the last couple sentences.

_I still can't believe they're married. It's going to take me a while to fully come to terms with that. But it was a beautiful day and a lovely ceremony, and I'm truly happy for both of them._

_Thank you again, Kate, for everything you did for her and for their wedding. Thank you for being there for me as I navigate this new aspect of parenthood. Thank you for talking me down when I need it. Thank you for loving me despite my stress and outbursts and nervousness._

_I love you._

_Rick_

"Did I really cry as much as I remember crying?" he questioned.

Kate smiled softly, torn from her recollections. "Babe, your daughter was getting married," she soothed. "I think it's okay that you shed some tears."

It had been a beautiful, intimate ceremony at a small rooftop venue in Manhattan. Alexis wore a simple white dress adorned with a deep blue ribbon around the waist, the color a nice complement to her flaming red hair. Her two best friends, dressed in matching dark blue dresses, were her bridesmaids while Cam's two younger brothers stood as groomsmen.

Lily was an adorable flower girl and Jake and Reece had done surprisingly well walking down the aisle as ring bearers.

And then Castle had walked Alexis down the aisle, and he knew they always say to look at the groom when the bride first appears, but he'd been too busy blinking back tears to remember to do so. Later, though, Kate had assured him that Cam had been grinning from ear to ear and blinking back a few of his own tears.

He found himself wondering how much Alexis remembered. After all, Castle recalled shockingly few details of his wedding to Kate. In the end, he supposed, it probably didn't matter. The wedding was just a day, a ceremony, a beginning. The marriage lasted a lifetime.

And Castle considered himself incredibly lucky to be spending the rest of his life with Kate.

* * *

_Thoughts?_


	15. Chapter 15

_A while back, I asked on Twitter for some scenarios in which Castle and Beckett would be reading their journal. You guys gave me lots of suggestions and I've ended up using most of them, but I forgot to write down who suggested what. So to all of you who sent your ideas... thank you! You'll start to see them show up in these remaining chapters._

* * *

**February 6, 2026**

All in all, it had been a horrible day, and it was only early afternoon.

Jake and Reece were both home sick from preschool, having received a diagnosis of strep throat early that morning. They'd finally succumbed to the pull of sleep a few minutes earlier, but there had been a lot of tears so far this morning; from the twins and from Kate. She hated seeing her boys so sick.

She'd taken the day off work, and she and Castle were tag-teaming it; currently he was out picking up their antibiotics, leaving her at home with the twins. But even the knowledge that he would soon be home and Jake and Reece would be feeling better by the end of the day wasn't enough to boost her mood. She needed a hug, some words of encouragement, some…

Words.

She needed Castle's words.

Kate slipped from the bedroom and quietly made her way downstairs in search of their journal and the comfort she knew it would provide. She found it in its normal spot on Castle's nightstand, wiped a thin layer of dust from the cover; they hadn't read in a while nor, it appeared, had Castle written her a letter recently. Life was certainly a lot busier with three young, rambunctious children.

She sank down onto the edge of their bed and flipped through the pages, skimming the first couple sentences of each one until she stumbled upon unfamiliar words.

_September 5, 2025_

_Dear Kate,_

_A little over sixteen years ago, you crashed my book party and changed my life in ways I couldn't even begin to imagine. I had no idea at the time that it was the beginning of the best story of my life – both in fiction and in reality._

_A few months later, you kicked me out of your life for the first time. I know I didn't understand at the time but in retrospect I deserved it. It was a lesson I needed to learn._

_Fifteen years ago, it was me who turned my back on our partnership, stepping aside to let you be happy. I know now that we fell victim to terrible timing and – as we've discussed before – it was for the best. We weren't ready then, and if we'd spent that long weekend together we might not be where we are right now._

_Fourteen years ago, you nearly died in my arms. To this day, that remains one of the worst moments of my life._

_Thirteen years ago, you showed up on my doorstep drenched in rain and kissed me. We've had so many incredible kisses over the years and a lot (a lot) of amazing sex, but that first night will always be near the top of my list. I'll never forget the feeling of our first time. I was already in love with you, but that night solidified it for me: I wanted to spend the rest of my life with you._

_Eleven years ago, you agreed to spend the rest of your life with me._

The soft sound of footsteps drew her attention away from the page, and Kate lifted her head to find Castle entering their bedroom with a pharmacy bag in one hand and his phone and keys in the other.

"Hey, everything okay?" he murmured as he approached.

Kate shrugged one shoulder, nodded half-heartedly.

Castle gestured with a tilt of his head. "They're asleep?"

"For now," she replied.

He sank down onto the bed next to her, set aside the items in his hands. "You sure you're okay?"

She dipped her eyes to the journal before turning her head to face her husband. "I'm getting there."

Castle leaned in to press his lips to her forehead, nudged his temple against hers as she turned her attention back to his letter and he followed suit.

_And ten years ago today, I made a promise to love you for the rest of my life. But I don't think I've completely kept my promise; at least, not in the way I meant it that day._

_I love you. I will always love you. __But at the moment I made that promise, I'd only ever had the opportunity to love you as my best friend, my partner, and my fiancée. For the last ten years, I've gotten to love you as my wife and the mother of my children, and the love I have for you today is deeper and more all-encompassing than I ever could have imagined._

_So today I'm making a new promise, Kate. For the rest of my life, I promise to continue allowing my love for you to evolve and strengthen. I promise to love you in ways I probably can't even begin to imagine. But most of all, I promise to love you with every fiber of my being._

_I gave you my heart so long ago, I can't even remember a time when you didn't have it. It's yours, Kate. It always will be._

_I love you more than I can put into words._

_Happy anniversary._

_Love,_

_Rick_

"Ten years," Kate murmured in awe as she reached the bottom of the page. "I can't believe it's been that long."

"Mmm," Castle hummed in agreement. "Ten years and three kids."

She lifted her head, resituated on the edge of the bed so she was facing her husband. "Did you ever think this is where you'd be?" she asked. "Ten years ago? Or sixteen years ago when we met?"

He shook his head. "Ten years ago? Maybe. Although I never imagined there'd be twins in our future." Kate grinned and he countered with his own lopsided smile. "But when we met," he continued softly, "not at all. I was done with marriage, done with relationships, and I never imagined I'd have any more kids."

She hummed in response.

"Did you?"

"No," she replied with a shake of her head. "I'd never even considered marrying any of the guys I'd dated, and I definitely didn't want kids."

"When did you know?"

"That I wanted to marry you?" Kate asked. "Or that I wanted kids?"

"Both."

"I'm not sure there was a specific moment when I knew I wanted to marry you," she answered, brow furrowed thoughtfully as she sifted back through their history. But no. There wasn't a moment that stood out. For her, it had been more of a gradual process from liking him to loving him to wanting to spend the rest of her life with him. "For having kids… do you remember that case with the lottery and the baby?"

"Rigging the lottery," he recollected.

She nodded. "That was my first time ever holding a baby and…" Kate trailed off with a timid shake of her head. "Never mind, it's stupid."

"No, it's not," he encouraged.

She sighed, hesitated before speaking once more. "I didn't know anything about babies," she confessed. "I was… scared, maybe? But you were so good with him and you showed me how to care for him and you were so happy and it just… made me start considering the idea."

Castle grinned broadly, eyes crinkling in the corners and somehow still sparkling for her despite their exhaustion. "Well, I'm glad you did," he affirmed, looping an arm around her, holding her close.

Kate's thoughts shifted immediately to their sleeping twins. Watching them endure such pain and misery the last two days had broken her heart. Even without the current bout of sickness, raising twins had been utterly exhausting and endlessly challenging from the very beginning. But she wouldn't trade it for the world.

She leaned into her husband's side, relished the comfortable familiarity of his embrace. "Me too."

* * *

_Thoughts?_


	16. Chapter 16

_Reminder that this story ignores the events of seasons 6-8._

* * *

**November 21, 2026**

Recently, Kate had found herself wondering where this year had gone. The older their children became, the faster time seemed to pass. Jake and Reece had, inexplicably, begun kindergarten three months ago, and Lily was a chatty, intelligent, precocious fourth grader already. Kate felt as though it had only been a year since she'd been able to hold both Jake and Reece in her arms at the same time.

But the truth was that another year had come and very nearly gone; the end-of-year holidays were fast approaching. They would be hosting Thanksgiving at the loft in a few days, certain to be a large, festive gathering. Jim, Martha, Alexis, and Cam would be there, of course, but this year they'd also invited Ryan and Jenny and their two kids, Esposito and his fiancé, Lanie and her boyfriend, and Detective Angela Underhill, who had recently been promoted from Vice to join the team at the Twelfth.

Kate was looking forward to the holiday, but she was dreading the chaos she knew would ensue from having Lily, Jake, Reece, Sarah Grace, and Nicholas all under the same roof. So when Alexis had offered to babysit for the weekend, leaving Kate and Castle with two days to themselves, they immediately took advantage of the opportunity and headed off to the Beckett family cabin in the Catskills.

November wasn't the ideal time to be up in the mountains; the sky was an endless expanse of grey and the cadence of rain on the roof hadn't let up for hours. But inside on the sofa, warmed by the crackling fire and enjoying a bottle of wine, the late autumn chill seemed so far away.

Castle and Kate sat side by side, wine glasses cradled in one hand and their journal held open on his lap by the other. They hadn't had time to read for a few months now but a weekend away afforded them a chance to catch up. The handful of letters they'd read through already had been upbeat and entertaining, full of Castle's thoughts and observations about their children over the past few months.

It quickly become clear, though, that the present letter had a very different tone.

_March 4, 2026_

_Dear Kate,_

_My dad is dead. _

_My dad – who I only met once, whose real name I didn't know until this morning – is dead. And I'm confused, because I don't know how I'm supposed to feel. _

_I remember I once told Alexis that I didn__'__t mind not knowing who my father was because in my mind he could be anything I wanted him to be. And I believed that, for a long time. Then I met him. The situation was far from preferable, of course, but since then, amidst numerous other emotions, I__'__ve always been thankful I finally had a chance to know who he was._

_It's been 13 years since Paris, and I still don't know how I feel about him. He saved Alexis's life, and mine too. I've never doubted that. But our lives never would have been in danger in the first place had it not been for him. And he caused so much death and destruction in the process, without even batting an eyelash. That's something I've always struggled to come to terms with. At first I thought it was so cool that he was a spy. Then I saw it in action, and the illusion was thoroughly shattered._

_It's so easy to live with regrets and to be angry about things you can't control, but I don't want to live that life. Things are what they are. I grew up never knowing my father, and that's not something I can change. He made his choices, and that's not something I can change, either. I am who I am today because of everything that's happened to me, and who knows who or where I'd be today if I'd grown up with him as a part of my life. _

_Still, I sometimes found myself wondering if I'd ever see him again. Now I never will. I'm not sure how I'm supposed to feel about that, either._

_I guess you could argue that I'm not 'supposed to' feel any certain way, because loss of a family member is something that everyone handles differently. But was he really even a family member? Biologically he's my father, but he was never actually my dad. _

_Most of the time, I don't mind that I never had a dad. But from time to time I've found myself wishing he'd been around. _

"You did?" Kate questioned in surprise, setting her wine glass on the coffee table and turning to face him more directly.

Castle took a deep breath, released it slowly, taking his time to sort out the words before speaking. "I never knew two of my grandparents," he said at last. "And I just wish… I wanted our kids to grow up with the family I never had."

"Babe, there's no set definition of a family. You've said it yourself so many times." She gestured to the journal. "I mean, look at us? You, me, Alexis and Cam, our kids, your mom, my dad. We're a family, Castle."

"I know," he conceded.

"Do I wish my mom was here to meet you? To meet our kids?" Kate asked, the question obviously rhetorical. "Every single day. But that doesn't make us any less of a family just because she's not here."

"I know," he repeated.

"The same applies to your dad."

He hummed in reluctant agreement, took a moment to gather his thoughts. Kate searched his face inquisitively, green flecks dancing in her eyes as she studied him.

"Okay," Castle conceded after a long moment.

She nodded in understanding, turning her attention back to the letter.

_As a single father, I also sometimes found myself wishing I had a dad to go to for advice. I like to think I did a pretty good job of figuring things out on my own, but I also never had anything to compare myself to, so I really had no idea. _

_I'm thankful to have your dad now. He's the closest thing to a father I've ever had, and he treats me as I always imagined a father would treat a son. He's the role model I never had when I was younger. And he's been more of a father to me than my biological father ever was._

_I guess if nothing else, it was nice to know that he cared in his own way. _

_I don't know what else to say today. It's going to take some time for me to sort through my feelings and come to terms with his death. I'm not sure what kind of closure I'll ever find. Maybe there won't be any. I don't know. Usually writing helps me sort through my feelings. Today it doesn't seem to be helping, but I'm not sure how else to cope. _

_In times like this, I'm exceptionally grateful I have you. Even when the rest of my world is tilted on its axis, you make me feel as though I'm standing on solid ground. You keep me from drowning in my feelings and, in this case, getting lost in the turmoil as I attempt to make sense of his passing. _

_Thank you for listening as I work through my thoughts, for comforting me, and for loving me unconditionally. You always seem to know exactly what I need. _

_Love,_

_Rick_

"I'm still not sure how I feel," Castle confessed as they reached the end of the letter.

"That's okay," Kate assured her husband. "There's no timeline for this kind of thing."

"I guess," he offered with a shrug.

He didn't speak again and Kate remained silent as well, sipping her wine and gazing into the flickering flames while Castle was left to his own thoughts. She wished she could be more helpful in this situation. He'd said in his letter that she had been, but she felt relatively useless.

Maybe this was something he needed to work through on his own.

But if he did need her, if she could help in any way, she silently promised that she would be there.

* * *

In the end, it was Jim Beckett who seemed to help Castle the most.

Kate arrived home from work two days later to find her husband sitting in the plush chair in his office chatting on the phone with her father, and she hid a smile behind her raised hand as bits of the conversation floated out through the open door. She didn't want to intrude, but it was difficult to tear herself away from what was clearly a very heartfelt conversation.

She knew Castle and her dad spoke from time to time, and that her husband sometimes called him for parenting advice. And she loved that the two men got along so well. They always had. She hadn't been there when they met and she didn't actually know the full story of their first couple encounters.

But when Castle hung up the phone and strode into the kitchen ten minutes later, more bounce in his step than there had been in a while, Kate knew that the specific details weren't important. What mattered was that her father would always be there for Castle and vice versa, and she was thankful to know that two of the most important men in her life shared such a strong support system.

And she was happy to see her husband smiling once again.

* * *

_Thoughts?_


	17. Chapter 17

**March 13, 2027**

"Want to read from our journal?"

Kate both felt and heard his words, the vibration of his chest beneath her and the flutter of his lips at her ear. They were enjoying a quiet Saturday night in their luxurious bathtub, warm water and bubbles surrounding them, shadows dancing on the walls from the flickering light of a row of candles. Kate was seated in the vee of his legs, her back resting against the soft but firm wall of his chest, one hand tracing absentminded patterns on the skin of his thigh. Castle's right arm was looped low around her abdomen while the left held a glass of Cabernet.

She took a sip from her own goblet, swallowed and paused to enjoy the deep blackcurrant flavor before replying. "Sure."

She felt movement behind her, turned her head to watch as he set his glass aside and wiped his hand on a tea towel before reading for the spiral bound notebook. Careful to avoid dipping it into the water, Castle flipped open their journal and set aside the bookmark. Kate readjusted against him and together they began to read.

_September 3, 2026_

_Dear Kate,_

_It's so quiet. For the first time ever, Jake, Reece, and Lily are all at school, and the loft is eerily silent. _

_I've forgotten how much I dislike the silence. _

_I've been sitting here all morning trying to get some writing done, but the words just aren't there. The fact that I can hear myself think and that every little noise distracts me doesn't help either. I've gotten so used to writing with background noise that I no longer seem to be able to get any work done without it. _

_I also find my mind fixating on a singular thought: should I go to the precinct? It seems so long ago that we decided I would stay home with the kids and that maybe, someday in the future, I could rejoin you as your partner. It's been almost ten years since that conversation, and a lot has changed since then. Your job has changed since then. I don't think a police captain really needs a partner._

_But I still miss it. Even though it's been ten years, I miss spending my days at the Twelfth. I get to wake up with you every morning and fall into bed with you every night, and I wouldn't trade it for the world. But it's just not the same as working by your side. _

_I think deep down some part of me has been clinging to this fantasy for years, even though I know it's not realistic. I've known for a while. But it was always a nice idea off in the future, something to look forward to. I guess it's time for me to come to terms with the fact that it will never be more than a dream. _

"I miss it too," Kate confessed. "I miss having you there and I miss being out in the field."

"I could still come back," Castle offered, unrealistic though he knew the suggestion was.

"And sit there watching me do paperwork?"

"Hey, I've done it before," he pointed out, grinning against her cheek.

"And it would be just as creepy now."

"We're married now, I think you can admit that you secretly enjoyed the attention."

Kate rolled her eyes in a gesture very reminiscent of those first few years they'd spent together at the Twelfth.

"I heard that."

She pursed her lips, shook her head. He knew her too well.

"Come on," she murmured after a moment, "the water's getting cold. Let's head to bed."

They set the journal aside and climbed out of the bathtub, went about their nighttime routines side by side, a well-choreographed dance after so many years. All three kids had been fast asleep for at least an hour now, and the hands on the clock were approaching ten p.m.. Ordinarily, they would be falling asleep themselves soon too, but it was a Saturday night and Kate was enjoying their evening of relaxation.

So instead they refilled their wine glasses and arranged the pillows behind them as they settled into bed with the journal, backs against the headboard and all thoughts of sleep pushed far from their minds.

_Life always has periods of transition, and this is just the most recent example. With all three kids in school, my role as a stay-at-home dad is changing. This is my new normal and I'll have to adjust. _

_For today, I might head down the street to a coffee shop and try to get some writing done. Maybe the background noise will help. Besides, this is only a temporary situation. I'll be picking them up from school in a few hours, and they'll still be home on weekends and holiday breaks and during the summer. There will still be plenty of chances for fun and games and noise and messes and chaos. _

Kate laughed. Noise and messes and chaos pretty well summed up many aspects of life at the loft these days.

_Besides, this isn't just about me. It's about Jake and Reece reaching a new milestone. They're growing up, and this is the next phase for them. They made such great strides in preschool this past year, and I'm excited to watch them continue to grow and learn. Somewhere beneath the boundless energy, they have your tenacity and intelligence. I'm seeing it more and more every day. They're so much like you, Kate._

_And really, how could I ever ask for anything more than that?_

_Love,_

_Rick_

"They really have come so far," Kate murmured around a sip of wine.

Much to Castle's chagrin, neither boy had shown much interest in reading prior to kindergarten, and both had struggled with writing and spelling. It was completely the opposite of his experience with Alexis, and with Lily as well. Their pediatrician had ensured him it was normal, and that boys typically lagged behind girls in things like reading and writing at that age. Nevertheless, it had been a source of worry and frustration for him.

But the improvement both boys had shown over the past six months was measurable and remarkable, and Castle now felt an enormous sense of relief.

"They have," he agreed proudly.

The conversation drifted after that, touching on Jake and Reece's first soccer practice and Lily's most recent dance recital before wandering back to a story Castle had never heard before about the time Kate's parents put her in karate lessons and she kicked a boy in the face after he tugged on her hair on the very first day.

From there, they talked about any and everything; stories of the past, anecdotes, hopes and dreams for the future, career and otherwise.

Kate had always been mesmerized by the power of his words, and her intelligence and wit had captured Castle's attention years ago, held him hostage. But it had been ages since they had just talked for hours like this, without succumbing to either exhaustion or desire.

Kate saw arousal flash behind his eyes on more than one occasion in response to her story of an undercover vice op. And she found herself fighting sleep eventually as the hours ticked by. But the glasses of red wine on their nightstands slowly found their way past their lips, and then another, and then a third. And it was just enough to keep the conversation flowing at an easy, lazy rhythm, a familiar back and forth that largely defined their relationship.

In fact, it was well past three when Kate set her empty glass aside for the last time, a giant yawn escaping her. Castle followed suit, rearranging the pillows around them and scooting down beneath the layers of blankets.

Outside, a steady cold spring rain poured over the city, soaking every surface and pattering steadily against the window. But here, in the warmth of their bed and each other and their own little bubble, all that mattered was the soft words flowing between them.

Their words, and their love.

* * *

_Thoughts?_


	18. Chapter 18

_I was stuck on this chapter. Like... completely stuck. But as usual, Andy figured out exactly what it needed. __Thank you, my brainstormer extraordinaire! I'd be lost without you :) _

* * *

**May 14, 2028**

If anyone ever asked Kate to describe her life in one word, she was fairly certain she would choose 'chaotic.' With a ten year old and twin seven year olds, the loft was typically in a state of disarray. Nobody could deny that their children were creative, but that also meant that it wasn't unusual to find a pan on the sofa or stuffed animals in the refrigerator or an action figure balanced on the keys of the piano. These days, Kate could scarcely keep up with all the imaginative games and scenarios their kids invented.

Most of the time, though. She didn't mind the chaos. She loved that all three of their children had inherited their father's imagination and creativity. She loved that all three of them liked to read and write and make up elaborate stories. She loved that they could entertain themselves for hours.

And she definitely loved the rare occasions where all three of them could play together without dissolving into an argument. So far, this was one of those times. It was Sunday morning and Lily, Jake, and Reece were on the floor of the living room enclosed in a blanket fort Castle had helped them build, with Monopoly and a collection of stuffed animals.

Castle was mixing mimosas while Kate whisked up a bowl of eggs in preparation for the arrival of Alexis, Cam, and Connor. It was Alexis's first Mother's Day and Castle had invited her to join their typical celebration of brunch and a movie.

"Here you are." Her husband's voice startled her as she set the beaten eggs aside, and she turned to find him with a mimosa in each hand, one extended in her direction.

Kate took the champagne flute from him with a smile. "Thanks."

"Happy Mother's Day," he replied, raised the glass.

She clinked her glass against his, lifted it to her lips to take a sip.

He drank as well before setting the glass aside and turning his attention back to the kitchen. There wasn't anything more to do; the eggs were ready to be scrambled, the coffee cake was in the oven, the coffee was on, the table was set, and Alexis, Cam, and Connor weren't due to arrive for another fifteen minutes. Nevertheless, Castle nervously flitted around the kitchen, double and triple checking every detail.

"Babe," Kate murmured, extending a hand in his direction and coaxing him around to the opposite side of the bar. She sank into a stool, gestured for him to do the same. "Everything looks great."

"I just…" he sighed. "I want it to be perfect."

"It will be," she promised. Castle glanced around nervously once more before finally seeming to comprehend her words and begin to relax. "Sit and relax. I'll be right back."

Kate reappeared a minute later and reclaimed her seat on the bar stool. "Here," she offered, extending their journal in his direction. She'd caught a glimpse of the next letter last time they read, knew it was appropriate for this situation.

Castle took the notebook from her outstretched hand and flipped through to the bookmarked page while Kate perched on the bar stool next to him and rested an elbow on the counter, cradling her chin, ready to read.

_December 19, 2027_

_Dear Kate,_

_Today, I became a grandfather. I'm simultaneously so proud of Alexis and so in love with baby Connor and feeling so old._

_How is it possible that my baby girl is grown up and married and a mother? _

_Having your own child is an incredible experience – as you know. Watching him or her grow up is even more amazing – as you're learning. But seeing her all grown up and caring for her own child… it's indescribable. She was just this helpless little thing and now she's holding her own helpless little thing. _

_It's as though everything has come full circle. _

_You asked me once before if it was weird for me to have such a large age separation between Alexis and our kids and I brushed it off. But now it's kind of strange to have children and grandchildren who are so close in age. I have six year old sons and a ten year old daughter and… a newborn grandchild. _

_I wouldn't trade it for the world, though. Raising Alexis was incredible, and our family is a dream come true. It may be unorthodox, but it's everything I ever could have asked for._

_Being a grandfather is… strange. The instant love I felt for Connor is different than the love you feel for your own child. It's still intense, and I'd do absolutely anything for him. I feel very protective of him. But he's not my child, and I'm still adjusting to my role in his life. _

_We've talked at length about my father – or lack thereof – for most of my life, and how I had to navigate fatherhood on my own with no one to look up to. I can say the same thing about being a grandfather. My mother's parents died when I was young, so I never really had any grandparents that I can remember. My mother is a grandmother to Alexis, obviously, but even though I don't have my own grandparent memories, I know that their relationship is unorthodox._

_I do have your dad, though, and watching him with our kids over the last ten years has given me some ideas, at least, of what my role should be. _

Kate smiled to herself, felt an unexpected wave of tears threatening. Her dad had been amazing from day one, helping them get settled at home with Lily, offering to babysit, and helping out in any way he could. Just as he'd done with Kate, he'd taken Lily to her first baseball game when she was just five years old, and it had now become an annual tradition for the two of them. Jake and Reece would be going to their first game with him in a couple weeks and, in their excitement, had spent most of the last week turning anything they possibly could into baseballs and bats. Kate had confiscated more than a few items from them; there had been no shortage of tears, though surprisingly no broken objects. Yet.

Watching her dad with the kids was also a constant source of happiness for Kate. He'd lost just as much innocence as she had that January night almost thirty years ago, but he'd been reclaiming it now with his grandchildren and it was so wonderful to witness.

Castle shifted next to her, lifting his glass to his lips to sip his mimosa, and the movement pulled Kate from her thoughts back to the letter.

_I'm realizing now that grandparenthood is challenging in unexpected ways. Already, there have been times where I wanted to give unsolicited advice, but I know that's not what Alexis and Cam need right now, and I know they'll figure most of these things out on their own. I also know I'm going to want to spoil Connor rotten, which is something I used to get mad at my mother for when she did it to Alexis. I understand her point of view now. Clearly this is just the next obstacle of parenthood for me to navigate. _

_I know it's a long way off still, but I'm excited for the day you become a grandmother. I know you're essentially a grandmother to Connor, but I imagine it's not quite the same since your relationship with Alexis has never really been a traditional stepmother/stepdaughter type thing. Someday, I hope you get to experience this feeling in full. I hope I'm by your side when that day arrives. I'm almost sixty and our kids are still so young, and recently it's a thought that's been weighing on my mind. I'm suddenly feeling much older now that I'm a grandfather._

Kate rested a hand on his knee, squeezed gently in comfort. Their age difference had never been an issue for either of them, but in some of her more vulnerable moments recently she had entertained similar thoughts about the reality of the ten-year gap between them.

_But this letter isn't supposed to be about my fears of growing older. It's supposed to be about Alexis and Cam and Connor._

_My grandson. _

_I can't believe it. I don't feel old enough to be a grandfather. I don't feel ready to move on to this phase of my life. But it's not about what I'm ready for; it's about what Alexis and Cam are ready for. They're diving off into the deep end of parenthood, and that means it's my time to embrace the role of grandfather. _

_Even though I don't feel ready, even though I'm not entirely certain what my new role will entail, I'm looking forward to the journey. And as always, I feel immensely grateful to have you by my side as I take this step into the unknown._

_I love you, Kate._

_Thank you for always being there for me._

_Love,_

_Rick_

With Lily's eleventh birthday rapidly approaching, Kate had never given much thought to herself one day becoming a grandparent. She didn't feel remotely old enough to be a grandmother. It was far in the future – she hoped – and for now she was content to enjoy parenthood. But now that Castle had crossed that barrier, part of her was curious as to how she might feel when that day arrived.

As with so many aspects of parenthood, though, she would have Castle to guide her. She would be able to learn from his experiences… starting now.

When she was pregnant with Lily, he'd been there to guide her through the process of preparing for the arrival of a newborn. After Lily's birth, he was the one who taught her how to hold their daughter and burp her and change her diaper and put her down for a nap. At the time, she'd been so overwhelmed and afraid of letting him down, but also so grateful; she couldn't even imagine having to learn everything on her own.

Fortunately, she'd had a wonderful teacher. Even from day one, it was apparent that Castle was a good father. And while she had at times feared that she'd never live up to his parenting abilities, she also felt lucky to have such a good example from which to learn.

Despite the confusion Castle alluded to in his letter, in the last few months he had adjusted to his role as a grandparent fairly easily, or so it seemed. Kate opened her mouth, poised to ask if he felt more comfortable now, when the sound of a key in the lock broke the silence; she made a mental note to broach the subject later.

They just barely had a chance to close the notebook and slip it beneath a stack of newspapers before the loft was a hive of noise and activity. Alexis and Cam were stepping through the door with five-month-old Connor in tow, prompting a mass exodus from the blanket fort. Lily managed to exit the maze of linens unscathed but Reece tripped over his brother who then stumbled and fell, pulling half of the fort came down on top of them.

With an eye roll and a chuckle, Kate set aside her mimosa and went to help untangle her sons while Castle and Lily greeted the new arrivals.

Brunch was a lively affair and though they were clearly exhausted, it was apparent that Alexis and Cam were adjusting to life as new parents and were loving it.

And as Kate stood at the sink later that afternoon, washing the last few dishes and silently observing the pride and joy and pure love in Castle's eyes as he cradled his sleeping grandson, she found herself looking forward to the day – far in the future – that she, too, would become a grandparent.

* * *

_Thoughts?_


	19. Chapter 19

**December 22, 2030**

The living room was dimly lit, illuminated only by the colorful lights on the Christmas tree and the flickering flames from the fireplace. Beneath the tree, presents were already piled high though the holiday was still three days away. All three children were on winter vacation now, and the loft was a flurry of noise and excitement very atypical for a Sunday night.

Lily was in the kitchen with Kate baking Christmas cookies while Jake and Reece tromped around upstairs, engaged in some kind of lightsaber/fencing duel that also somehow involved their old Halloween costumes and a pair of marshmallow shooters.

Ordinarily, Castle would have eagerly joined the melee but he was currently feeling decidedly unenthusiastic about duels or marshmallows or Christmas or much of anything. Even the festive atmosphere wasn't enough to lift his spirits. He was seated at the dining room table, alone and silent amidst the chaos, eyes inexorably drawn to the dancing flames. But it was what was missing from the scene that forced him to blink back the tears that lingered so close to the surface these days.

For the first time in years, only nine stockings hung from the mantle above the fireplace rather than ten.

He was moments from losing the battle with his tears when Kate quietly appeared, crossing from the kitchen with a dish towel in her hands and a flour-covered apron draped over her clothing. She stepped up behind him, tossing the towel aside and running her fingers through his hair.

"You okay?" she murmured, low enough to remain undetected by Lily who was determinedly frosting a batch of tree shaped sugar cookies.

Castle shook his head, swiped at an escaped tear.

Kate followed his gaze, felt the familiar pit of grief awakening in her stomach. "I miss her too," she whispered, stepping around to his side. She cradled him to her, felt his arms loop around her in a desperate embrace as his cheek came to rest against her ribs.

"Is it always worse around the holidays?" he asked into her apron.

"I think so," she answered truthfully, fingers tenderly combing through his hair. "It always is for me because my mom died so soon afterwards. But I think it would be more difficult no matter when it happened."

After a long moment of silence he lifted his head, fixed her with dull, red, watery eyes that broke her heart. "How do I get through it?"

"You remember all the good times," she replied easily, reciting the things she'd always relied on. "And sometimes it makes you smile and sometimes it makes you cry. And whenever you need a hug, you come find me and I'll be here to cry with you if that's what you need. Or cheer you up, if that's what you want."

It was a near echo of her words the previous week after they'd read his journal entry dated just a few days after Martha died; Castle was pulled back to the memory now, of her words and his and the tears they'd shed together.

_October 14, 2030_

_Dear Kate,_

_I don't know how you do it. How do you cope with the loss of a parent? How do you ever come to terms with it and stop feeling completely empty and devastated by it? __I know you've said that one day the loss becomes a part of you, that you don't mind carrying it around with you. I'm sure someday I'll reach that point, but right now it seems impossible. _

_I understand now, in a way I never have before, what you went through. And yet, I can't possibly comprehend what you went through because my mother lived a long, full life and her death wasn't entirely unexpected. I had a chance to say goodbye to her. We all did. _

_I actually feel guilty writing this letter to you. I shouldn't complain; after all, I was fortunate to have 61 years with my mother. You only got to spend 19 with yours. And I'm infinitely grateful for the time I had with her, but I just miss her so much. _

_Will that feeling ever go away? Or is this numb emptiness something I'm going to have to learn to live with? Is this what you meant when you said her loss will become a part of me? If so, I can't even fathom a life in which I have to carry the heavy weight of this grief around with me every day. I feel like I'm drowning, and I can't find any air._

_I know I need to find a way to be strong and to be there for our children, but I don't seem to have any strength left. I feel like I'm failing them by wallowing in my own grief instead of being a shoulder for them to cry on, and my guilt for that is almost worse than the crippling feeling of loss. As much agony as I'm in, it's been even worse to see them hurting as well and know that I'm doing nothing to help assuage the pain. _

_Please don't think I haven't noticed everything you've done, because I have, and I owe you a tremendous thank you, Kate. Thank you for hugging me through the tears and for holding me up when all I've wanted is to crumble to the ground. Thank you for being there for our kids when I wasn't strong enough to do so. Thank you for being the backbone of this family._

_I don't know what comes next or how to move forward from this. As a son, I don't know how to cope with the loss of a parent. As a father, I don't know how to help our children through this confusing and painful time. As a husband, I don't know how to be there for you, because I know you miss her too. _

_I don't really know anything anymore. I just feel so empty. _

The letter had ended there. No conclusion. No signature. He'd simply… run out of words.

Two and a half months had passed, and he was still struggling to find the words. A half-finished novel sat on his laptop, untouched since that day. He couldn't even fathom finishing it right now.

"Dad?"

Castle was torn from his spiral of thoughts by his daughter's voice and he hastily composed himself, swallowing the grief and blinking the tears from his eyes.

"Finished the tree cookies?" Kate asked, stalling Lily long enough for Castle to have a few extra moments to himself.

She nodded proudly, extending her right arm to reveal the cookie balanced on her open palm. Beneath it her skin was a rainbow of color, a nice match to the smudge of blue frosting on her cheek and the flecks of red in her hair.

"I put sprinkles on this one like lights," she announced. "And a little star at the top. It's for you."

Castle smiled in spite of himself at the sight before him, Lily beaming with pride and covered with frosting and flour, Kate watching in amusement. This year, for the first time, Kate had taken a back seat in baking Johanna's famous Christmas cookies, allowing Lily to make them almost entirely by herself.

"Thanks, Lil," he offered, lifting the cookie from her palm and taking a large bite before proclaiming, "delicious!"

"Mom, we're out of green frosting but we still have to do all the wreaths," she explained seriously, already turning her attention back to their baking project.

Castle felt Kate squeeze his shoulder gently before slipping away, following their daughter back to the kitchen and the remaining cookies. He watched them go while enjoying the frosted concoction, chuckled softly as Jake and Reece bounded into sight a minute later, bickering with Lily about which cookies they could eat before Kate finally stepped in to resolve the silly squabble.

They were all growing up so fast; Lily was in eighth grade this year, just a few months away from high school. Jake and Reece were almost ten. And Alexis was pregnant again, due in just over a month. She and Cam would be arriving tomorrow night with Connor, and Jim would arrive first thing Christmas morning.

Castle missed his mother. He knew he would always miss his mother. But even so, he realized with an unexpected jolt of happiness, there was quite a lot to celebrate this holiday season.

* * *

_Thoughts?_


	20. Chapter 20

_Few years of a time jump here, but I couldn't possibly include every detail of their lives together so I had to pick and choose the important moments to write about._

* * *

**January 19, 2036**

The loft was eerily silent.

Lily was back in Pennsylvania now for the start of spring semester and Jake and Reece were away for the weekend at a basketball tournament, Jake as a member of the Marlowe Prep pep band and Reece as a player on the JV team. Jake had chosen to play the clarinet back in fifth grade and never looked back, but Reece's interest in basketball was fairly recent, only beginning the previous year. He'd taken to it well, though, making the JV team as a freshman.

Castle and Beckett had made it to most of his games this season, but Castle had spent most of the day driving Lily back to State College and the tournament this weekend was in southern New Jersey, so it hadn't worked out this time. Reece had texted a couple hours ago, though, to inform them that the team won both games today and would be playing one more in the morning before returning to Manhattan.

A large yawn escaped, unbidden, and Castle set aside his laptop and extended his arms above his head in a stretch.

"You okay?" Kate asked, lowering the novel to her lap and bookmarking the page with her finger.

"Mmm, just tired," he admitted. "All that driving."

"It's late," she offered. "We should sleep."

He snapped his laptop shut and placed it on the night stand, catching sight of their journal as he did so. "Want to read a couple letters first?"

Kate replaced her finger with her bookmark, set the novel aside. "Sure."

_June 3, 2035_

_Dear Kate,_

_I don't think I ever told you this, but I was terrified when we learned we were having a girl. Alexis was always pretty easy, She raised herself and – as you know – was far more mature than I was. I'm still not sure where she got it from._

_But a girl with your genes?_

_I wasn't sure I'd survive eighteen years. I think it's safe to say that we know why my hair has turned completely grey. _

Kate reached up to ruffle her husband's hair. He'd initially struggled to accept the color change, but she'd always liked him with grey hair. He looked handsome and distinguished.

_She's so much like you, Kate. She always has been. She was precocious as a toddler, outspoken and determined from a young age, and stubborn as hell. I wasn't the best-behaved high schooler, so I guess I can't blame her rebelliousness completely on you. But her defiance and her attitude definitely came from you. _

_But the truth is, I'm glad she inherited so many of your traits. She has your intellect, your kindness, and your depth and strength of character. She has your drive and your passion and your fierceness. I'm glad she's grown up to be so much like you. I couldn't ask for anything more than to have a daughter who is as extraordinary as her mother. _

"She's so much like you, too, you know," Kate pointed out, interrupting their reading and resting a hand on his knee. "She has your optimism and your curiosity and your openness."

"You don't give yourself enough credit," Castle disputed. "You've opened up so much since I first met you."

"To you," she pointed out. "And it took years."

"But you struggled to open up because of your past," he stated. "What about before that? Because the stories I've heard of high school Kate Beckett aren't the stories of someone who was closed off and introverted."

"If only you knew how many stories you still haven't heard," she teased.

"You know," Castle mused, "ordinarily I'd be asking to hear all of them, but after living through it I'm not sure I need to."

They'd caught Lily sneaking out a couple times and once – in what was by far their most awkward encounter – caught her attempting to sneak a guy and a box of condoms into her room. As was so often the case in parenthood, Castle found himself with extremely mixed feelings about the whole situation. He was predominately horrified, of course, but deep down there was a sense of triumph that they'd raised her to have the foresight to purchase condoms.

But no. He was mostly horrified. He cringed now at the memory.

She'd also ignored her curfew for senior prom and spent the night at her date's house – Castle shuddered; he really didn't want to think too hard about that one – arriving home the next morning with a wrinkled dress, hair a tangled mess, and a hangover she wouldn't admit to.

She came home drunk after her graduation weekend festivities too although, now that he thought about it, so did Alexis.

"Would it help to know that I was far worse than Lily ever was?" Kate asked.

"She spent the night with what's-his-name," Castle blurted. "What could be worse than that?"

"How about being in the shower with a guy when your parents come home?" Kate asked.

He gaped. "What? How have I never heard this story? When was this?"

"Junior year, when I was dating that grunge rocker," she replied. "My parents were supposed to be out late, but they came home a couple hours early and we were… well, we weren't exactly showering. Let's just put it that way."

"Wait, they walked _into _the bathroom when you were in there?"

Kate wrinkled up her face. "Eww. No. But in the panic, I didn't think to push the condom a little further down into the trash can, so it was pretty easy for them to figure out what went on."

"What happened?" he asked, curiosity piqued.

"They grounded me for a month, although I'm pretty sure I still managed to sneak out at least once."

"And you kept dating grunge rocker guy?"

"Not really," she shrugged. "Without the sex, he lost interest pretty quickly."

"What kind of a shallow jackass would break up with you just because…"

"Rick, he was seventeen," she interrupted. "And he wasn't that great anyway. Are you really upset that I didn't keep having sex with him?"

"Well, no," he hedged. After a pause, Castle opened his mouth to speak, closed it again.

"What?"

"Nothing."

"No, what?" she prompted. "You can ask."

"Was he your first?"

He remembered asking her years ago what her number was; she'd dodged the answer and it wasn't a conversation that had ever come up again. They both knew there had been others, and they'd both seemed content to leave it at that.

"Yes," Kate answered.

"So you were seventeen?"

She nodded.

"How old were you?"

Castle hesitated.

"You don't have to answer," she amended quickly.

"No, it's fine." He cleared his throat. "I was, uh, nineteen."

"Kyra?" she guessed.

He nodded.

"I, uh, oh," Kate stammered.

"Not what you expected?"

"No," she admitted. "I always assumed you'd been younger."

"Yeah," he agreed. "I think most people would."

"I guess we can both be thankful we're no longer the people we were in high school."

Castle visibly shuddered and Kate felt an amused smile tug at her lips before their attentions fell back to the page in front of them.

_She's headed off to Penn State in just a few short months, and part of me will always worry, but deep down I know she'll be fine. She has a solid head on her shoulders and she's well-adjusted and whatever she decides to pursue, I know she'll excel. _

_I'm proud of us, Kate. It wasn't always easy, but I feel comfortable saying that we raised her well._

_One down, two to go._

_Truthfully, as terrified as I was of Lily reaching her teenage years, I'm even more at a loss with Jake and Reece. I don't know what a normal father-son relationship is supposed to look like since I never had one. I don't know how to parent a teenaged boy. _

_I certainly don't want them to be like I was in high school._

"Babe," she murmured, "you're an incredible role model and a wonderful father. If they turn out anything like you are, then we have nothing to worry about."

"Now I'm those things, maybe," he pointed out. "But I wasn't then."

"Was anyone in high school?"

Castle didn't reply, so she switched tactics.

"Look, I wasn't either," Kate pointed out. "You know how much of a mess I was. I wasn't even close to being okay until we started dating, and even then I still made plenty of mistakes and bad decisions."

Castle sighed. "I guess I just don't want them to make all the mistakes I did."

"I think every parent would say the same thing," she agreed. "But they're going to screw up sometimes. The best thing we can do is teach them the importance of learning from their mistakes and moving on."

"Since when were you the one talking me down from parenting concerns?" Castle teased.

But the truth was that they'd both talked each other down from time to time. It was just another example of all the ways they worked together so well; they rarely got riled up or panicked over the same things, so whenever one of them overreacted the other was there to be the voice of reason.

Concerns moderately assuaged, at least for the time being, Castle turned his attention back to their journal.

_But I don't want to think about that right now. This letter is supposed to be about Lily. Our high school graduate. I'm so proud of her. I was too busy crying yesterday to find the words to express myself, but my heart swells with pride now with the memory of her walking across the stage to receive her diploma and being recognized for her 4.0 GPA._

_I think it's safe to say she inherited your brains and your work ethic, too. _

_Thank you, Kate, for being such a wonderful mother and wife. Raising Alexis was an incredible experience, but it's been so different this time around, having you by my side the entire way. We make a good team. We always have. We always will._

_I love you._

_Rick_

They'd had a wonderful holiday with Lily home, but towards the end of the week she had been eager to return to her new friends and new classes and – Kate suspected – newfound freedom. She remembered those days; no bedtime, no curfew, no need to check in with her parents or ask permission before dashing off to an alcohol-laden party. If her parents only knew what had gone on during that year in California…

She had a feeling ignorance was bliss in her case as well.

But she also knew that Lily had a solid head on her shoulders, as Castle had written. And she knew she could call at any time for any reason. Castle had promised her during her freshman year of high school that if she was ever in a situation that made her uncomfortable, she could ask him to come get her and he would, no questions asked, no judgement, no punishment.

Lily had only cashed in on that promise once, the night of junior prom, in the midst of a situation involving her boyfriend, alcohol, and the car keys she'd determinedly confiscated from him. Castle had jumped out of bed at 2:00 in the morning, returning home a short while later with a sobbing, furious Lily who broke up with the guy later that day.

She was glad their daughter was enjoying her freshman year, something Kate had only partially experienced. After all, her mother's death had occurred while she was home for her first Christmas break; though she'd returned to California for winter and spring quarters, she moved back home that summer and transferred to NYU.

The first of many ways in which her life had been upended by her mother's death.

At the time, her future had seemed so bleak, and the only way forward that she'd known was to graduate, get accepted into the police academy, and then devote herself to the job so she could solve the case. Even when she first met Castle, that was the clear future that lay ahead of her.

If only the past version of herself could have seen her now. She'd never have believed she'd one day have a college aged daughter and high school aged sons, a husband and a family and a life that once seemed so improbable and terrifying.

She had everything she hadn't known she wanted, and she was infinitely grateful for that.

But she also knew that her past – all of it – was a part of her and had molded her into the person she was today. She'd made mistakes of course, and there were some regrets; but in the end, she wouldn't change a thing because everything that ever happened was a part of her story. It was a part of what led her to Castle.

And everything they had together… it was by far the greatest chapter of her life.

* * *

_Thoughts?_


	21. Chapter 21

_Apologies for the long wait between posts, I wasn't feeling well last week. Thank you all for your patience and continued support!_

* * *

**August 23, 2037**

"Hey, everything okay?"

Kate shrugged half-heartedly, offered a small tilt of her head.

"Rough day?"

She nodded.

"Anything I can do to help?"

She lifted her arm, drawing his attention for the first time to the book cradled in her hands. Its brown leather cover was well worn and bent at the corners and it was open to the third to last page. The last two pages were filled now too and Castle had just purchased a new journal the previous week, though he hadn't written in it yet.

Castle sank onto the sofa next to his wife and followed the path of her eyes to the page and his own words staring up at him. He recognized the date at the top and immediately felt himself engulfed by the same wave of melancholy that was clearly weighing on her shoulders.

_April 29, 2037_

_Dear Kate,_

_I don't know what to write today. I'm not sure I have any words right now other than "I'm sorry," and that seems so inane. So useless. _

_It's been a little more than 24 hours since your dad died, and I still just feel so empty. I know he wasn't actually my father, but he was the closest thing I ever had and I loved him a lot. _

_I miss him already. I know you do too. And I know the pain will fade with time, just like it has with my mother, but that's not much of a comfort right now. I just want to curl up in bed with you and hold you close and cry, but I can't because we have three sobbing teenagers who are as devastated as we are, and I have to be strong for them. I have to be strong for you, too. I just don't know how. _

_But if there's anything you need, anything I can do to help make this less terrible for you, please let me know. I'll figure out a way to be strong. I'll figure out anything if it means I can lessen your pain or help shoulder even a fraction of your burdens. _

_For now, I draw some small semblance of strength from the thought that he's with your mother again. _

_I miss him._

_I love you._

_Rick_

"I miss him too," she murmured as she reached the end of the letter. "Every day."

"I know you do."

They fell into silence and Kate eventually found herself re-reading her husband's words. She had almost reached the end of the letter again when Castle finally spoke.

"I just hope I'm even half the man he was," he confessed, and the sorrow in his eyes broke her heart for an entirely different reason. "I hope I've been as good a father and grandfather as he was."

"You are, Rick," Kate assured him. "No question."

He didn't seem convinced but he also didn't protest, and she interpreted that as a win for now. But they would have to revisit this topic at a later date.

"Did I ever tell you that your fatherhood was the first thing that attracted me to you?" she added after an extended silence.

Castle met his wife's eyes in surprise. "Really?"

"Really," she echoed. "Even at the beginning when you annoyed the hell out of me, you were always different with Alexis or when you talked about her. It was really sweet."

"Even though I didn't want it to be," she added as an afterthought, just as Castle murmured, "I never knew."

"You were down to earth when you talked about her, and your eyes were full of pride and love and it just… it reminded me of my dad. He always used to brag about me like that. Only, he would do it when I was standing right there, and it was so embarrassing."

"Well, he had every reason to be proud of you," Castle affirmed.

Kate managed a watery smile in reply.

"I'm proud of him, too," she admitted into the stretching silence. "After my mom…" she trailed off with a sad shake of her head. "I was afraid I'd lose him, too. There were a couple of close calls."

"Mmmm," Castle hummed in acknowledgement, unsure how else to respond. Jim had always remained sober, and as Castle hadn't known him during those trying years, he'd always had trouble reconciling the man he knew with what he knew of his history. But if Castle had learned anything from his father-in-law – and from Kate – it was that it was possible to overcome any challenge, and to refuse to allow the past to dictate the future.

Early in their partnership, Castle had watched Kate struggle through the process of breaking free from her past. But he could see now that he, too, had been confined by his past. He, too, had to break free from his failed marriages and the resulting cynical attitude toward love and commitment and forever. In hindsight, it was so clear. He knew he may never have moved on from his path had he never met Kate. She'd told him before how much he'd helped her face down her demons, but the truth is that it went both ways.

"I see so much of your dad in you," he added after a moment. "And I see so much of both of you in our kids."

Castle had observed quite a lot of the Beckett strength in the four months since Jim's passing. Initially there had been a lot of tears and devastation and stubborn denial. This was the first summer they'd spent without him, and his absence from their Memorial Day and Fourth of July traditions had been extremely noticeable. There had been no baseball games for the kids to go to with their grandfather, no trips to the cabin or to Coney Island. Jake and Reece didn't get to go fishing – which unexpectedly led to a large amount of drama even though they'd always maintained that fishing was boring and stupid.

Labor Day weekend was fast approaching, and Castle knew they would once again be facing an annual family tradition without Grandpa Jim. He wasn't sure what to expect now that more time had passed, but it would inevitably be a very different end to summer than they were used to. But if he knew anything about his father-in-law, it was that Jim wouldn't want them to abandon their family traditions in his absence.

It hadn't been easy to pull him into the Castle family holiday traditions, holidays he no longer celebrated after Johanna's passing. But over the years, Jim progressively took part in more and more of the celebrations until his attendance and enthusiasm became an unwavering presence at each one. He'd even admitted to Castle once, a few years back, that he was thankful he'd become a part of these family traditions and wasn't missing all of these opportunities to spend time with his grandchildren.

And so, their traditions would live on. And though he was no longer with them, Castle knew Jim would live on as well, always in their memories and stories, and forever in their hearts.

* * *

_Thoughts?_


	22. Chapter 22

_I'm so so sorry for the long wait between chapters, real life completely got in the way these past few weeks. Thank you all for sticking with me!_

_This chapter turned out nothing like I planned, but this is where my brain went so I decided to follow it _¯\\_(ツ)_/¯

* * *

**October 29, 2039**

"Kids wore you out, huh?"

Castle pried his eyes open, rolled his head across the back of the armchair until his eyes settled on Kate. "Hmmm?"

"Accidental nap?" she asked, one eyebrow quirked facetiously.

He ran a hand over his face, wiping away the remnants of sleep. "What time is it?"

"Six."

Castle groaned, tilted his head and began to paint a circle through the air with his chin, first clockwise, then retracing his path in a counterclockwise direction. He was way too old to fall asleep sitting up with his neck cranked backwards.

Kate crossed to stand behind him, rested gentle hands on his shoulders and began to tenderly knead his aching muscles.

"Mmmmm," was Castle's only reply.

"Alexis and the kids?" he asked a few moments later, the knots in his neck loosening under his wife's ministrations.

"She's taking them to Cam's."

"She's coming back for dinner?"

Kate nodded, added a verbal affirmation when she realized she was standing behind him and hadn't seen her motion.

"You were writing?" she asked, eyes catching sight of the journal and pen spread across Castle's thighs.

He grimaced. "I think I fell asleep before I finished."

"Mmmm." Kate rounded the chair, lifted the pen and journal from his legs and sank onto her husband's lap. "Any previously finished entries to read?"

"A couple, I think."

She tossed the pen onto an end table, flipped open the notebook and shuffled through the pages. "Shall we?"

_June 6, 2039_

_Dear Kate,_

_I'm a mess. I'm confused. I'm angry. I'm sad. I'm disappointed. But mostly, I feel like a failure. _

_I know I was never a shining example when it came to marriage and relationships. I've written before about how much that bothered me, especially when it came to the example I was setting for Alexis. But I always found reassurance in the fact that she was the mature, responsible one who made good decisions and had her life together. She is all of those things. But I guess even that doesn't shield a person from the realities of relationships and marriages and divorce._

_Watching my daughter go through a divorce isn't something that ever even crossed my mind, and it's something I'm not even remotely equipped to deal with. What do I do? What's my role? How do I contain my feelings? I want to yell and scream at Cam, even though I know it's not his fault. I want to talk to Alexis, too, and tell her to try harder and make it work. But I know it's not her fault either, and I know they've tried, and it's also just not my place to interfere. _

_It goes against every instinct to sit back and watch my daughter go through this pain. I know all too well what she's feeling. But neither of my first two marriages were that stable to begin with and neither of them lasted as long as hers and Cam's did, so in many ways I'm sure I don't fully understand how she's feeling and what she's going through. She doesn't want to talk about it either, and that's been perhaps the most difficult thing of all. I want to be there for her, I want to help her, but that's clearly not what she wants right now and that's frustrating for me. _

It was true. Alexis had attended Jake and Reece's high school graduation the past spring without Cam and their kids, and later that evening when the twins had headed off to celebrate with friends was when Alexis finally came clean about the real reason Cam wasn't in attendance.

It just wasn't working anymore, she'd said. There was no drama or infidelity, no secrets or nastiness. Just two people who had grown apart and were no longer in love, despite attending couples counseling. And that was all she'd said.

_I also worry that I didn't react well when she told us what was happening. My words, I feel, were appropriate, but I think she could see the disappointment in my eyes, and I'm not proud of that. I owe her an apology and an explanation._

_What do I do, Kate? What do I say to her? How do I let her know I'm here for her without being too pushy? And what about Connor and Emma? He's twelve and she's eight; there's no good age for your parents to split up, but I have to imagine they may not handle it well at all. How do I help them? _

_I can't believe I put Alexis through two divorces. She never acted out or gave any indication that she was struggling during or after either one, but now I wonder what she may have been concealing. I wonder if my divorces negatively influenced her marriage. I wonder if she blames me and that's why she doesn't want to talk about it. _

"She doesn't," Kate promised. She wasn't certain how much Alexis had actually told her dad at this point, but Castle's daughter had recently opened up to her and while she planned to keep the details of their conversation a secret – at Alexis's request – she felt it was acceptable to at least ease Castle's concern in this situation.

"I wish she would talk to me," he lamented, running a frustrated hand through his hair and heaving a deep sigh. Kate could hear the defeat in his voice, see the sadness in his eyes, and she so desperately wished there was something she could do to take it all away.

"I know," she answered, only just managing to bite back the words 'she will' before they came spilling out into a promise that wasn't hers to make.

Alexis was living at the loft now, had been for the past four months. Cam had kept their apartment uptown and she and Cam were sharing custody of their children while the legal divorce proceedings were in progress. While it had initially been an adjustment to have young children living with them again, Kate was fairly certain Alexis was grateful to have their support and she knew Castle was also enjoying the opportunity to spend so much time with Connor and Emma.

Alexis had also confided recently that she was hoping to find her own place after the New Year, and Kate found that she was going to miss the constant company. After so many years with three children running around, she'd grown used to the noise and chaos, found comfort in it. And with Alexis moving in just as Jake and Reece were headed off to college, she and Castle hadn't actually had a chance to be empty nesters.

Both boys would be coming home for Thanksgiving in a few weeks, reuniting after three months apart. For the first time in their lives they were living in separate places, and Kate knew it hadn't been an easy adjustment for them. Jake was attending Boston University on a music scholarship and was planning to pursue a dual degree in music education and theater. Reece, meanwhile, was attending NYU and had no idea what he wanted to major in but he seemed to be enjoying his first semester. He'd moved into the dorms on campus, and though he came home occasionally – mostly when he ran out of clean clothes or was craving a home-cooked meal – he spent most of his time immersed in college life.

Lily, on the other hand, would not be making the trip back for the holiday and while this was the first time the family would not be all together on Thanksgiving, Kate understood her daughter's decision. Lily was in her first semester of law school at Stanford, and not only was it a long and expensive trip back home, but she was also drowning in school work.

Kate had a feeling Lily's friend Matt – who she suspected was more than a friend, given the number of times his name had come up in their recent Skype conversations – played a role in her decision, too. Lily hadn't confirmed and Kate hadn't asked, but she had a feeling this Matt had stolen her daughter's heart.

"Did you finish?" Castle asked after a long moment, startling Kate from her thoughts.

She dipped her eyes to their journal, shook her head. "Oh, uh no. Almost."

_I just don't know what to do, Kate. I miss the days when a funny face and a hug were all I needed to make her pain go away. But those days are long gone, and I'm suddenly acutely aware of how quickly my life has flown by and how rapidly things change. I've never been good with change._

_I don't think most of us are. We cling to what's familiar, what's comfortable. But Alexis can't do that right now, because what's familiar to her has fallen apart. I imagine there isn't much in her life right now that feels familiar… maybe that's how I can contribute. I can be there just like I always am so that when she's craving that familiarity she has somewhere to go. It's the only way I can think to help her; I just hope it's enough. _

_I hope I'm enough. _

_Love, _

_Rick_

"It is," Kate promised the moment she finished reading. She didn't want to speak for Alexis, but his daughter had said as much a few days earlier. "And you are."

He always had been. She couldn't speak for Alexis, of course, but Kate's life with Castle was everything she'd ever dreamed of and more, and it would always, _always_ be more than enough.

* * *

_Thoughts?_


	23. Chapter 23

**January 12, 2040**

"That is not true!" Kate exclaimed, eyes flashing with defiance, hands perched on her hips; a posture he'd become very familiar with over the years.

"It is so," Castle insisted, not to be deterred. He was right. He knew he was right.

"I absolutely was not."

"You were, ask anyone."

"No," Kate replied firmly.

So maybe those margaritas had been a little strong. But she definitely wasn't going to give him the satisfaction of knowing that she'd possibly been slightly tipsy by the end of the evening.

"Fine, you know what?" he set his coffee mug aside and rose determinedly from his seat at the bar. "I'll prove it."

"How?" she asked to his retreating back, but he didn't answer right away. Instead he vanished through the office into their bedroom, reappearing seconds later with their journal in his hand.

"I wrote about it," he replied, holding the notebook up triumphantly. "A few months back. That will definitively prove that I'm right about you being drunk at the launch party."

She raised a skeptical eyebrow but otherwise didn't reply.

Castle flipped through the notebook in search of the particular letter that would make his case while Kate turned her attention to the half-finished crossword puzzle they'd been working on before devolving into this silly debate.

"Aha!" her husband exclaimed, slamming the book onto the bar with more force than necessary, pages spread wide open beneath his spread fingers. "This one."

But as they read through the letter it became very clear that Castle had not, in fact, written anything about Kate's state of inebriation. It wasn't mentioned in the next letter either, or the one after that. As they reached the end of the fifth letter with no mention of it, Kate turned to her husband, one eyebrow raised and lips pursed. The silent "I told you so" look he'd been on the receiving end of more times than he could count.

"I really thought it was in here somewhere," he insisted petulantly.

"So you concede."

"Never," he growled. "I'll simply have to find another way to prove that I'm right."

"Good luck with that," she murmured, crossing one leg over the other and calmly sipping her coffee, clearly unfazed by his rekindled determination.

He spent a few more minutes flipping backwards and forwards through the notebook while Kate refocused on the crossword puzzle. She was wracking her brain on 53 Across when Castle murmured, "you know, we could read some new letters too while we have this out."

"Do we have any?"

"There are a couple."

Kate set aside her pencil, turned her attention to their journal.

_November 30, 2039_

_Dear Kate,_

_It's been 30 years since you crashed my book party. In that moment, I never could've imagined this is what my life would become. They say you remember every detail of the most life-changing moments. Well… I remember with perfect clarity the day we met. I was standing at the bar, lamenting to Alexis about the predictability of book launch parties, telling her that just this once I wished someone would come up to me and say something a little less cliché._

_And then you tapped me on the shoulder and introduced yourself, and that wasn't at all what I'd had in mind when I said I wanted something different, but it definitely fit the bill. _

_I was attracted to you from the beginning; that's not news. But when you bit your lip and murmured 'you have no idea' into my ear in what I now know is your bedroom voice, and then sauntered away like you couldn't be bothered to give me the time of day, I was hooked. _

_Our second case was the first time I witnessed your compassion and empathy, and the way you used those traits to talk that girl into dropping the knife. You treated her with respect and kindness even though she was the murderer. This was the first time I realized how much depth lay beneath your hard outer shell. _

_The first time someone fired their gun at you was the first time I realized that what I felt for you was more than just a silly crush. I was scared for my life, but I was more scared for yours. _

_When you walked away from me in that hospital hallway with tears in your eyes, I realized I'd developed more than just casual feelings for you. It hurt to know that I'd hurt you, and that was something I hadn't experienced in a very long time. I learned a lot from that, and in the end I know it was for the best that things happened the way they did. Every near miss we ever had was a chance for me to learn and re-evaluate and become a better person. To become someone who was worthy of your love. _

_We spent our first three summers apart, and the second summer was painful but the third summer was by far the worst. Those long months of loving you but never knowing how you were doing was agonizing. I'm not blaming you. I know you did what you had to do to make it through, and I moved past the hurt and anger long ago. But looking back, that was one of the most painful periods of my life. _

_Of course, I can't forget all of our near misses: when your apartment blew up, the dirty bomb, your car being driven into the Hudson River. The tiger. The bank explosion. _

_I've never forgotten when you came into the bank dressed as a paramedic. I was sure it was the last time I was ever going to see you, and there were so many things I wanted to say in that moment, but I couldn't and it broke my heart. When you came to the rescue and freed my hands and smiled at me with everything you always tried to hide written all over your face, it took everything I had not to kiss you right then and there. I've always wondered what would've happened if we hadn't been interrupted. _

"I would've kissed you back," Kate murmured.

"Really?"

She nodded, an adorable shyness in her eyes that Castle hadn't seen in a long time.

"That whole year, my plan was to work through my issues in therapy so they didn't get in the way of us when we finally got together," she confessed, though this was information he already knew. The second part of her sentence, however, was new. "But I almost threw the whole thing out the window that day. If I had to pick a single most devastating moment of my life – aside from losing my mom – it would be the moment that bank blew up around you."

"I never knew," Castle acknowledged, before their attention shifted back to their journal.

_I've long since lost track of the number of times we've saved each other's lives, but I'm glad that number has stopped climbing in recent years. I know there were times you missed being out in the field, and I always missed working by your side, but speaking as your husband and the father of our children, I was always thankful that Captain and Commissioner were much safer positions._

_I know there are countless other moments I'm forgetting, but there are just so many examples of your kindness and passion and determination and fierceness and strength and everything that makes you extraordinary. There's a reason you were the youngest woman to ever make detective and the best detective and captain to ever pass through the Twelfth Precinct. There's a reason you became the first female to ever head the NYPD. _

_You've accomplished so much in the last ten years, and I'm so proud of you for the changes you've brought about and all the ways the department has improved during your tenure. This city is damn lucky to have you. And I know I speak for so many when I say you will be missed. _

_But I'm excited for what lies ahead now that you're retired. I'm excited to be spending my days with you again. I'm excited that we'll have more opportunities to head out to the Hamptons and to explore the city and to travel the world. _

_Retirement is simply the next step in this great adventure called life and, as always, I'm eternally grateful to be spending it by your side._

_Love,_

_Rick_

Adjusting to retirement hadn't been easy for Kate after so many years of working long hours. With Jake and Reece out of the house and Lily in California, Kate suddenly found herself without any of the responsibilities of the last thirty years. But together, they'd settled into a new routine.

The pace of their life was slower now than it used to be. Castle's old knee injury flared up from time to time. Kate was still in good shape, but her years on the force had started to catch up with her. Neither could push their bodies as hard as they used to; it was another thing they'd struggled to come to terms with, but together they'd helped each other accept their new normal.

Mornings were quieter and more leisurely now. They would rise with the sun, sometimes before, and enjoy coffee and breakfast over the daily New York Times crossword puzzle. Later, they would go for a lengthy walk through the city, sometimes wandering through parks and stopping for a rest on a shady bench. Other days they would walk along the river or the shoreline, sometimes taking a cab to allow them to explore places too far to reach on foot alone. Some days they ended up in the library or an old bookstore or a quaint coffee shop or café. Their newest addition was volunteering as dog walkers at the local Humane Society, so some days a furry friend or two would join them on their midday strolls.

It was strange not having a schedule or a plan but they had grown to love the flexibility of their new lifestyle and the opportunities it afforded them, whether it was time to volunteer or simply the chance to explore the city they'd always called home.

Castle was still writing and some days he would bring his laptop and Kate a book and they would relax somewhere for a few hours while Castle alternated between typing furiously and people watching and staring absently at the wall or ceiling.

They would head home sometime in the afternoon to take a nap or watch a movie or, occasionally, to prepare for an evening out or in with friends. Ryan and Jenny's kids were grown now too and though Jenny was still teaching, Ryan had also recently retired. Esposito was still on the force and Lanie was now New York City's chief medical examiner. Lanie had never married, but Esposito and his wife had been together for nearly 20 years now and she'd become a part of their precinct family as well. The seven of them made it a point to get together every few weeks for dinner, sometimes joined by other former officers from the Twelfth, some of Jenny's colleagues, or the parents of their children's friends who had become some of their closest friends over the years.

Other nights, they would have a casual evening in, just the two of them. It was strange and quiet and a little bit lonely initially, but they were both adjusting to it all fairly well.

"So are we going to do it?" Castle asked excitedly, pulling Kate's attention back to present day and the letter they'd just finished reading.

She cocked her head. "Do what?"

He indicated his words. "Travel the world?"

They'd taken a handful of overseas trips before Lily was born, and as a family they'd managed to sneak away at least once a year to some foreign land. They always spent Memorial and Labor Day weekends at their house in the Hamptons, and they usually spent a couple weekends a year up at the Beckett family cabin, too. Kate counted herself very lucky to have had these opportunities and to have provided their children with that type of cultural education. And she loved traveling as a family. But she was also really looking forward to some time away with just her husband.

"I want to," she answered. "I'd say we've earned some time away."

Castle grinned, waggled his eyebrows at her. "I can't wait to have sex in as many countries as possible!"

He was met with an eye roll, but despite her feigned annoyance she couldn't suppress her smile.

Twenty seven countries down, one hundred sixty eight to go!

* * *

_Thoughts?_


	24. Chapter 24

**October 13, 2045**

The bedroom was cast in a warm amber glow, lit only by the flickering flames of a few candles on the dresser and the light of the moon streaming in through the sliding glass doors. It was nearly full and shining brightly, glistening off the landscape and shimmering in time with the rhythmic cresting of the gentle waves.

Laying in their bed gazing out over the water had never gotten old, even though they'd been living out here in the Hamptons full-time for almost four years now. Not long after Kate retired, they'd made the decision to move away from the city they'd called home their entire lives. It was time for a slower, quieter life.

Alexis had taken over the loft and Connor and Emma, who were now teenagers, spent roughly half of their time there as well, spending the remainder with their father. Connor had just begun his senior year of high school, and Castle was having trouble reconciling the little brown-haired baby boy with the six-foot-tall, baseball-playing young adult he'd become. He knew Jim would've loved the fact that one of his grandchildren was so enthusiastic about the Beckett family's favorite sport.

But as much as Connor and Emma had grown and matured, the biggest change in their family in recent months was the addition of a new member. Matt and Lily had tied the knot two months prior, in a lovely ceremony here in the Hamptons, with the moon rising in the background and the entire property decorated with strands of white lights that mimicked stars twinkling overhead.

After a two week honeymoon in Europe, they had settled back into their apartment in California, where both were well-established in their respective careers – he as a firefighter and Lily as a lawyer. Castle was beyond proud of his daughter and son-in-law, but he did often find himself wishing they lived closer. However, it had been wonderful to have the entire family back in Manhattan for the weekend in celebration of Lily and Matt.

And it was fun to reminisce now as Castle and Kate sat cuddled in the middle of their bed, surrounded by a pile of blankets with Cocoa the fluffy cat – the other recent addition to their family – curled on their feet.

_August 20, 2045_

_Dear Kate,_

_Lily is married. _

_I've been through this before with Alexis. I thought it would be easier the second time around. __But maybe it's just never easy to watch your daughter get married. I wonder if I'll feel this way if and when Jake and Reece get married? __I wonder if it ever gets easier to watch your children grow up and move on with their lives… lives that we're no longer as much a part of? _

_Matt is great. I'm thrilled that Lily found someone as wonderful as him, and I'm forever thankful that she's in a solid relationship with a man who is much more responsible and mature than I ever was at that age. You told me once that girls who are close to their fathers are likely to end up dating guys just like them, and that terrified me for years. Especially with Alexis. _

"You know that's not true, right?" Kate asked.

"That girls end up dating guys like their father?" Castle echoed.

"I mean, maybe that's true," she amended with a shrug. "But in your case it's not a bad thing, even though I meant it to be at the time."

"Except, at the time, you weren't wrong," he argued. "I was terrible husband material. For most of my life."

Kate leaned in to press her lips to his cheek, nuzzled her nose against the day's worth of stubble dusting his skin. "Babe, any woman would be lucky to marry someone like you."

Castle slipped an arm around her shoulders, held her closer.

_I have to say, though, it's been comforting and also somewhat amusing to watch you freak out over this wedding. As tense as I've been, you've been a hundred times worse. Ninety percent of the time you're so calm and collected, so I sometimes forget how panicked you can get. I didn't see you immediately before our wedding, but from what I did observe, you were more nervous about this one._

_I suppose that makes sense. I wasn't terribly nervous for our wedding either. I just wanted to be married to you, and despite all the planning that went into it, when the time arrived I didn't care about the details. You were there and our families were there, and that's what mattered. But as parents we obviously want our children's weddings to be perfect. _

_All in all, I think things went according to plan. There were no major catastrophes and only a couple minor hiccups. I'm not even certain Lily and Matt noticed them. Perhaps the biggest drama of the day was when the mother of the bride accidentally drank a little too much champagne._

Kate groaned and rolled her eyes. It turned out she'd become much more of a lightweight in recent years, something she hadn't realized until _after_ she'd lost count of the number of glasses of champagne she'd consumed.

"You were so drunk," Castle laughed.

She ran her fingers through her hair before resting her forehead against the heel of her hand. "My hangover the next morning can attest to that."

"I'm not sure I'd ever seen you that drunk."

"And you never will again," she promised. "I'm far too old to drink that much."

"If you're too old to drink, what does that make me?"

"Age is wisdom, babe."

"Nice save."

Kate smirked and averted her eyes, dropping them back to the last few lines of text on the page.

_Drunk or not, it was a beautiful ceremony and I'm so proud of Lily and so happy for them both. But, as usual, it's hard to believe she's already old enough to be married. It seems like just yesterday that she was a little girl, and now she's a lawyer and a wife and I don't think I'm ever going to fully come to terms with it. _

"Me neither," Kate admitted. "I never thought I'd feel that way, but I do."

"Then we can commiserate together."

_Sometimes I wish the world would just stop for a little while, but I swear it's moving faster and faster every day. I suppose the best we can do at this point is to be thankful for the time we've been given and enjoy every moment of the time we have left. _

_As long as you're by my side, I know I'll never have any issues with either of those things. You're my life, my love, and my everything. Always. _

_Love,_

_Rick._

Kate found herself lingering on the last two paragraphs, re-reading them again and again and relating very easily to Castle's words. How she was five years into her retirement with three grown children, Kate didn't know. It was a place that, for many years, she never imagined she'd be. And though they'd had their fair share of ups and downs, though there were regrets and moments she wished she could forget or do over again or remain trapped in forever, she was immensely grateful for the life that she had.

With Castle.

* * *

_Thoughts?_


	25. Chapter 25

_This chapter was a struggle. It was a massive struggle. And I'm really sorry for leaving you guys hanging for so long. The good news is that the remaining chapters are fully written so updates will be much more frequent now._

* * *

**Thanksgiving Day 2047**

"Hey, sleepyhead," Castle murmured as Kate's eyes slipped open. He watched the confusion turn to understanding as she glanced around the room, realized she'd dozed off on the sofa in what used to be Castle's office. "Unintentional nap?"

"Mmmm," she hummed. "I ate too much."

He patted his own stomach, a little fluffier now than it was in his younger years. "Me too. But everything was delicious."

"That pie was incredible," Kate agreed, shifting positions to allow her husband to sink into the sofa next to her.

Over the years, Castle and Kate had alternated with Alexis and Cam for hosting Thanksgiving dinner. Lily and Matt had yet to host, as it would require the entire family to travel to California, but they did make it back to New York for the holiday most years. But this had been Alexis's first time hosting since the divorce; she'd been nervous, but everything went off without a hitch.

This was also the largest Thanksgiving gathering they'd ever had as a family. Even with a 4 month old baby in tow, Lily and Matt were able to fly back to Manhattan. Jake and Aiden – his boyfriend of nearly two years – made the drive down from Boston for the weekend. And Reece brought along his girlfriend Gianna, introducing her to the family for the first time ever.

After having both daughters and then Aiden bring home their boyfriends, Castle found himself – for the first time ever – in the position of assessing a future daughter-in-law. Gianna was a NICU nurse, a kind and thoughtful and energetic person, and from all that he'd learned and observed so far, Castle was fairly certain he liked her.

Reece and Gianna had departed a few minutes ago along with Lily, Matt, and baby Joey, who would be staying with them for a couple days before heading back across the country. Aiden and Jake were on their way back to Boston, and Connor and Emma had disappeared to their rooms. Leftovers were put away, the kitchen was dark, and the loft was quiet save for the soft hum of the dishwasher. After so many years of noise and chaos, Castle had come to appreciate such moments of silence.

He and Kate wouldn't be heading back to the Hamptons until Saturday; in the meantime, they were staying here in their old home. Some of the furniture was new and certain decorations had been moved or replaced. It was strange to see these changes each time they visited, but even with the differences the loft brought back many fond memories.

It was a place of so many firsts. Their first (non-undercover) kiss, their first time, their first Thanksgiving and Christmas and a handful of other holidays. It was their first home together. The place they raised their family. Castle loved their life in the Hamptons, but being here now was reminding him of the reasons he sometimes missed the city and the place he'd called home for so many years.

* * *

Kate found him in the living room twenty minutes later, pen in hand and their journal on his lap, most of the page filled with freshly scrawled words.

"Writing?" she asked softly, tilting her head to read his words. "To me?" she added.

Castle hummed in affirmation. "Just needed to get some thoughts out."

She bent down to press her lips to his forehead and he caught her around the waist before she could slip away, nudging her onto the sofa next to him. "I'm done now, but we could read some letters."

"Sounds perfect."

_July 19, 2047_

_Congratulations, Kate,_

_Or should I say, Grandma Kate?_

_I know Alexis already has two children and you've essentially been a grandmother for twenty years, but I have to assume it's somewhat different this time around because Joey is biologically related to you._

"I guess maybe it is," she confessed thoughtfully. "Knowing that it's my genes being passed on this time."

_Watching you hold him is like watching you be a mother all over again, and it's the most beautiful thing I've ever witnessed. I can see the pure love in your eyes, the pride, the fierce protectiveness. I know exactly how you feel. I'd do anything for him, too. _

_I can't wait to watch you watch him grow. I can't wait to watch you spoil him, even though you swear you won't. After all these years of you being the stricter parent – and I don't mean that in a bad way, I've always felt like we had a good balance – I have a feeling you're going to spoil your him rotten. I'm not judging you; that's a grandparent's job, after all. _

_It's been 16 years since Emma was born; I'm excited to have another baby grandchild. I can't wait to introduce him to all our family traditions. It's going to be different this time, though. Our other grandchildren were born and raised in New York. Joey will be living in California. I know Lily and Matt will visit a couple times a year, and we have the finances and flexibility to travel across the country periodically, but it still won't be the same. We've seen Connor and Emma at least once a month since they were babies. Even with semi-regular visits, we won't be seeing Joey that frequently._

_I know there are plenty of people who only see their grandchildren a couple times per year. For many families, that's normal. And I would never ask Lily and Matt to move back to the east coast. They have their life and their friends and their careers in California and they love it there. It's just going to take some getting used to on my part. It's something I'm going to have to accept. _

_I'm also nervous this time around, in a way I wasn't with Connor and Emma. I'm 78. When Emma was born, I was only 61. I definitely don't have the energy or stamina now that I did then. What if I can't keep up with Joey? What if he doesn't like coming to visit Grandma and Grandpa? What if he thinks we're old and slow and boring? What if we never have a close relationship with him like we do with Connor and Emma? _

_I don't know the answer to any of these questions, and they've been weighing on my mind pretty heavily the last couple days. _

It was different. Castle and Kate flew to California for Joey's birth, but they hadn't seen him since. Four months had passed, and he was still a baby but was already starting to develop some personality. Castle wasn't sure when they'd see Joey next, but he was certain there would be many more changes in their youngest grandchild when they saw him again. And Joey was still far too young for any of Castle's other worries to be assuaged.

"Babe, Joey is going to love you," Kate promised, urgency in her words in an attempt to soothe his concerns. "And if there's one thing I know for certain, it's that you will never, ever be boring."

Castle chuckled and smiled to himself before returning his attention to the page.

_I suppose all we can do is be there for Lily, Matt, and Joey in any way we can, even if from a distance. It won't be the same and I'm sure we have a lot to learn about how to manage a grandparent-grandchild relationship from afar, but I have a feeling we'll figure it out. Between your brain and your heart and my creativity, we'll make it work. We always have been an unstoppable team. _

_In the meantime, we still have a few days left here in California and I fully intend to enjoy every minute of it. The first thing I plan to do is sit down on the couch and join you and Joey in your impromptu nap. _

_Love,_

_Rick_

"Do you think we can handle babysitting for a few hours?" Castle asked, setting the journal aside and re-situating on the sofa so he was facing his wife.

"You mean Joey?" Kate asked.

He nodded. "I thought Lily and Matt might enjoy having some time to themselves while they're here."

"A few feedings, some diaper changes, and some naps?" she recited confidently. "I think we can handle it."

* * *

_Thoughts?_


	26. Chapter 26

**Dec 19, 2048**

"So," Castle began. "Last day."

"Last day," Kate echoed.

"Is it bad that I'm ready to go home?"

"Not at all," she assured her husband. "It's been nine incredible days but I'm ready to be back in our own bed with our normal routine."

"You mean, our routine of being retired and having absolutely no commitments?" Castle joked.

Kate chucked. "Yes, that."

"In the meantime," Castle reached down with some difficulty, extracted a brown, spiral-bound notebook from his luggage, "care to do some reading?"

She sank down next to her husband, settling into the soft, fluffy cushions of the sofa in the living area of their luxury Croatian suite. "Don't mind if I do."

_September 8, 2048_

_Dear Kate,_

_I'm not sure who I am anymore. Is it possible to have a midlife crisis at the age of 79? Because I feel like that's what's happening. I've officially announced my retirement from writing. We just returned home from the book release. _

_It's over._

_The book is written, and there isn't another one in the works. I don't have a contract. I don't have plans to write another novel. I've been writing novels for sixty years. _

_I feel so empty. As though I'm missing a part of myself. What do I do now? I imagine it's going to take some time for me to figure that out. _

_But even though I'm no longer writing novels, I'll never stop writing for you. I used to worry that one day I'd run out of words for you. I worried what that would mean for us. But I know now that my concern was completely unfounded. You still inspire me after all these years. I always write well when I'm writing for you. _

_Thank you for crashing my book party forty years ago. Thank you for putting up with me as your shadow. Thank you for putting up with all the flack you received over Nikki Heat. _

_If I hadn't met you, my writing career very well might have ended with the death of Derrick Storm. I hadn't written in so long and, though I never told anyone, I was afraid at the time that I'd never write again. It was the worst case of writer's block I've ever had. _

_But you brought me out of it. You helped me find the words. You lifted me up from the lowest point of my career. Writing Nikki reminded me of all the things I loved about being an author. And writing Nikki was the catalyst for me falling in love with you._

_I know it's been years since the series ended and I don't regret my decision to end things when I did, but I still miss her. _

_But in the end, I have you. We have a family. We've had successful careers. We live very comfortably and we've been able to travel the world and share so many wonderful experiences. All thanks to Nikki. But really, thanks to you. _

_I should thank your mother, too, since she's the real reason we're together. If she hadn't read my books, you likely wouldn't have read my books, and we never would've met. Everything we are, everything we have… we owe it all to her. I like to think she's been up there cheering for us this entire time._

"Me too," Kate agreed.

_I guess we technically owe our meeting to the murderer who was staging his crime scenes like my books, too, but I like to ignore that little fact. _

"Castle," she groaned, swatting him in the shoulder. "You always have to ruin it."

"And you'd be disappointed if I didn't," he replied with a lopsided grin.

Kate rolled her eyes, but they both knew her exasperation was feigned. It was the same familiar back and forth they'd shared almost since the moment they met, and in all those years very little had changed.

_Regardless of how it happened, I'm glad it did. Our life together has been beyond my wildest dreams – and you know how wild my imagination can be – and I wouldn't trade it for the world. Even now that I'm moving on to the next phase and leaving a very important chapter behind, I know everything will be okay because I have you. I'll always have you. And as long as I do, I'll have everything I could ever want._

_I love you._

_Rick_

"Okay, you salvaged it," Kate conceded as she reached the end of the page. "I withdraw my eye roll."

"Withdraw?" Castle exclaimed with a mock gasp. "It's been forty years and you've never once withdrawn an eye roll."

"I can un-withdraw it."

"No, no, keep it," he assured her. "But I'm happy to know you're still capable of surprising me after all these years."

"Gotta keep you on your toes, Castle."

He set their journal aside, leaned in and captured her smiling lips with his own. "No place I'd rather be."

* * *

_Thoughts?_


	27. Chapter 27

**September 14, 2051**

Months.

It had been months since Kate and Castle last read a page from their journal. Tumultuous months filled with anxiety and fear. Months in which their journal scarcely crossed their minds as they were forced to face the reality of their increasing ages and declining health.

Castle didn't write to her as often now either, largely because their lives were much less hectic than they had been many years ago. But she knew he'd written to her at least once recently; she'd written to him, too. Her letter was still tucked away between the pages of their journal, where it had been for the past sixteen months.

Castle's brow furrowed in confusion as he lifted the folded sheet of paper, smoothed away the creases with hands less nimble than they used to be. "I don't remember writing this."

"You didn't," Kate answered softly. "I did."

He glimpsed the date at the top, nodded in understanding. He recognized that date. He always would.

_May 10, 2050_

_Dear Castle,_

_I'm scared. It's been a long time since I've been this afraid of anything. I know if I just talked to you, you'd know exactly what to say to calm me down. You always do. But I don't want to burden you with my fears when I know you're already dealing with your own, so I'm hoping I can write them out instead._

_Today you were diagnosed with prostate cancer. Even just writing the words seems so wrong. There's no way I'm ready to say it aloud._

_I know the doctors said your prognosis was good, that it was caught early and with radiation therapy there's a 95% chance the tumor will shrink or even disappear and you'll remain otherwise healthy. The odds are strongly in your favor and rationally I know things will probably be okay. But rationality couldn't be further from my mind right now. Maybe I've inherited some of your writer's brain over the years, because all I can do is play out the alternate scenarios. No matter how unlikely the alternative is – because in this case there are really only two possible outcomes – it's the only thing I can see. I can't turn it off._

_The thought of living without you has me paralyzed. I'm so grateful we've had 38 years together and I treasure every minute of it, but I'm not ready for our time together to end. I'm not ready to let you go. I'll never be ready for that._

_They say it's important to remain positive, and I'm trying to do that for you. I'm trying to keep things as normal as possible. I'm trying to stay optimistic. I'm trying to believe that everything really, truly will be okay in the end._

_But if by some small chance things do end badly, please remember that I'll be here for you through it all. I'll do anything you need, anything I can to help you. __I'll be by your side until the very end. And please never forget that __I love you with everything I have. I always will._

_Love,_

_Kate_

Castle was cancer-free now. He had been for almost six months. But the effects of the diagnosis and treatment still lingered. He'd responded well to the radiation; a few pounds lost but fortunately no other severe side effects.

But the fear of the cancer returning – regardless of how unlikely the oncologist said that was – was there. It would probably always be there, and it hung over not only him, but their entire family.

The important thing, though, was that he was alive and healthy, and he'd been fortunate enough to witness all the moments he'd worried he might miss.

Lily and Matthew's second son – Max – would turn one next month. Reece and Gianna had walked down the aisle three months earlier in a beautiful ceremony by the pond at the Beckett family cabin. And Jake and Aiden were nearing completion of the adoption process and preparing to welcome not one, but two children into their family – two-year-old twins Elena and Cora.

Despite the cancer diagnosis, and despite the lingering fear, Castle found he was proud of the life he'd lived and the family he'd created. He wasn't ready to die – from cancer or from any other cause – but it was something he thought he was maybe gradually beginning to come to terms with. He'd published fifty-eight novels. He had four children and four – soon to be six – grandchildren. He'd been married to his incredibly amazing wife for thirty-six years. He had a lot to be proud of.

After a long moment lost in their own thoughts, Kate slipped the letter from his hands, gently folded it back into quarters, and the crinkling of the paper drew Castle's attention back to their journal. The notebook still lay on the bed in front of them, open to his letter from the exact same day.

She set the folded sheet of paper aside and, by mutual silent agreement, they turned their attention now to his words.

_May 10, 2050_

_Dear Kate,_

_Cancer._

_I have cancer._

_Just writing those words makes me want to cry and yell and throw something and wrap you in my arms and never let you go._

_I'm so afraid._

_Everything will probably be okay. That's what the doctors said, and I want to believe them. I've always heard that keeping a positive outlook is important in situations such as this. But it's hard to banish the frightening and negative thoughts from my mind. I can't stop cycling through all the what-ifs._

_What if I don't make it? What if this is the end? I've raised four kids, watched two of my grandkids grow up and watched the third grow into a precocious almost three year old._

_But what about everything that hasn't happened yet? What about all the things I'll miss? Lily is pregnant again, but what if I don't make it to October and I never get to meet our second grandson? Reece just proposed, and he and Gianna are getting married next summer. What if I miss their wedding? Jake and Aiden just began the process of adoption. What if I never get to meet their child?_

_What about the other grandchildren and maybe even great-grandchildren I'll never get to meet?_

_What about you, Kate? My heart breaks at the thought of leaving you so soon. I'm not ready for our love story to end._

_I can't imagine living without you; I don't know what I'd do, but I'm certain I'd fall apart. I know that makes me a hypocrite, but I need you to promise me you'll be okay in my absence. I need to know that you'll be able to keep living and that you'll find happiness. I need to know that you'll still smile and laugh, because the world is a better place when you do._

_Promise me, Kate. Promise me you'll find a way to move on. Promise me you'll be there for Alexis, for Lily and the boys, for Connor and Emma and Joey. Promise me you all will band together as a family and help each other through this. If worse comes to worse and this really is the end for me, I need to know that my family will be okay. It's the only thing that will bring me any semblance of peace._

_I hope it doesn't come to this. I hope the doctors are right and the treatment is successful and I can stay in this world, with you and our family, for a few more years. But in case it's not, always remember that I love you more than anything in the world. Being your husband has been the greatest adventure of my life and I treasure every moment of it. I'm proud of us. I'm proud of the family we've created. I'm proud of you._

_I love you._

_Always._

_Rick_

"We'll be okay," she murmured, hoping her voice sounded stronger than it felt.

They were no strangers to the fragility of life or the harsh reality that everything could end in an instant. It was a fact they'd lived with for the duration of their relationship, one that had spawned numerous arguments and forced an immense amount of contemplation and reluctant acceptance.

Kate couldn't imagine living without Castle. She knew losing him would devastate her. She knew it would break her in ways she could scarcely begin to imagine. But she also knew that she had thirty-eight years of memories to hold onto and a family she could lean on. She knew they would help each other through their grief.

It would be difficult. She had no doubt that at times it would seem an insurmountable task. But eventually, they'd figure out how to be okay.

For Castle, she could promise that.

"You're wrong, though," Kate murmured after a long moment, glancing back to Castle's words and offering a slight change of subject.

"What?"

She nodded to the page. "Our love story won't end when one of us dies. It lives on every day in our kids and grandkids. And in here," she added, tracing his words with her index finger.

Castle found a smile spreading his lips, still so in awe of his wife after all these years. For a woman he'd initially characterized as skeptical and pessimistic, her optimism and belief – in them, in love, in magic – had been a continual and pleasant surprise.

"I love you," he whispered, tilting his chin to press his lips to her cheek.

Kate smiled, turned to capture his lips in her own. "Love you too, Babe."

* * *

_Thoughts?_


	28. Chapter 28

**September 5, 2055**

Coffee and Castle.

They were the first things she became aware of as she drifted into wakefulness. The same things she'd woken to so many times over the course of their relationship. Sometimes it was with Castle asleep next to her and the coffee brewing in the kitchen. Sometimes it was with Castle awake next to her, holding out a steaming mug prepared just the way she liked it. Sometimes it was to the sounds of Castle puttering around in the kitchen while the scent of freshly brewed coffee wafted through the early morning air of their house.

Today it was Castle in bed next to her, offering her a mug of coffee, his own in the other hand and a gift bag resting on his lap. And also a giant bouquet of bright red nasturtium bursting from a vase on her nightstand.

"Morning," he whispered, eyes sparkling with excitement in the early morning light.

"Mmmm, morning," Kate murmured, the words turning into a groan as she stretched her hands over her head, banishing the stiffness of sleep from her limbs. Her muscles were tighter now than they used to be and it always took a little longer for her to get going in the mornings.

But her husband, it seemed, was wide awake and grinning eagerly. Kate closed her eyes for one more long moment of peace before forcing them open again and slowly working herself into a seated position.

"Happy anniversary," Castle proclaimed as she settled back against the headboard and relieved him of the second mug of coffee.

"Mmmm, you too," she mumbled around a delicious sip of the hot liquid.

"I got you something." He wriggled the gift bag that sat on his thighs, red and gold and shimmery with crinkled sheets of white tissue paper sticking out the top.

Kate savored another long sip of coffee before setting her mug on the nightstand next to the beautiful flowers and taking the proffered bag. Castle looked on impatiently as she sifted through the tissue paper and reached inside.

Her fingers closed around a solid but soft object, smooth beneath her fingers. She eased the tissue paper out of the way to find a journal. The color was a darker shade of brown than their current one and the spiral binding was gold, but it was undoubtedly a replacement journal for the one he'd recently filled.

And wrapped around it, gently tucked in place, was a beautiful ruby necklace.

"Babe, it's gorgeous," Kate breathed, fingers fumbling slightly with the clasp. The chain eventually fell loose and she lifted the stunning pendant to admire it in the rays of morning sunlight.

"Here," Castle extended an open hand.

Kate gently placed the necklace into his palm and he fiddled with the clasp for a moment before draping it around her neck and securing it in place. She smoothed two fingers over the beautiful dark red stone while Castle situated the chain against the back of her neck.

"I love it," she whispered. "Thank you."

"Open the journal," Castle murmured in reply.

"What?"

He nodded to the notebook resting beside them on the sofa. "Open it."

Kate reached for the spiral bound notebook, gently flipped back the cover to reveal the first page. It was filled with Castle's familiar handwriting, the top line dated today.

_Dear Kate,_

_Forty years. I can't wrap my mind around that number. We've been married for forty years. _

_How is it possible that much time has passed since our wedding day? It seems like so much more, and yet also so much less, than forty years has passed since you slid that ring onto my finger and promised to love me forever. _

_You know as well as I do that I never could have imagined this future for myself before we met or even for the first few years after we met. I know you never foresaw this future either. But we are proof positive that if the right two people find each other and truly believe in something, then anything is possible._

_I remember a conversation I once had, so many years ago, with Captain Montgomery about his and Evelyn's anniversary, where he quipped that if I'd ever stayed married long enough I'd understand how it can be difficult to figure out what to get your spouse for an anniversary gift. I know he meant it as a joke and probably never expected me to remember it all these years later, but his words struck a chord with me. He was right; I'd never stayed married long enough to reach that point. And as much as I detested the concept of marriage at that time in my life, I think some small part of me yearned for that opportunity and that's why his words rang so true. _

_I finally did it. I finally reached that point where it's a struggle to know what to get you for birthdays and Christmas and anniversaries. I always prided myself on being a gift ninja, but my gift-giving skills have become decidedly less ninja-like the longer we've been married. He was right. It's hard. It's our fortieth anniversary and I have absolutely no idea what to get you. _

_If you're going through the same struggle, please know that the fact that I've spent forty years loving and being loved by you is the only gift I could ever need. We've had our trials and tribulations, we've had our moments of doubt and frustration, we've had our fair share of fights. But the overwhelming summation of the last forty years is that it's been amazing. It's been everything I ever could have envisioned and then some. It's been the journey of a lifetime. _

_Thank you for taking my hand all those years ago and diving into this journey with me. There's no one in the world I'd rather have by my side._

_Happy anniversary, Kate._

_I love you._

_Rick_

"Love you too, Babe," she murmured against his lips before sealing her words with a kiss.

She didn't know how many years they had left; after all, Castle was fast approaching ninety and she was nearing eighty. But she was thankful for every moment they'd been granted thus far, and she was determined to enjoy every moment that remained.

"Always."

* * *

_Thoughts?_


	29. Chapter 29

_I cried while writing this. I cried while proofreading this. Andy cried while beta-ing this. You have been warned._

* * *

**March 12, 2061**

The room was dark, the single lamp on the bedside the only source of illumination. Outside, night had long since fallen but he couldn't bring himself to turn on another light, content to remain here in the shadows. With the light came the collection of her belongings strewn across the bedroom, exactly where they'd been for the last few days. With the light came her clothes in the closet, her coffee mug on the nightstand, her toiletries in the bathroom. With the light came the feeling that she'd never left, that she'd return at any moment, joining him in bed as she had every night for as long as he could remember.

As much as he wanted to cling that fantasy, that hope, he knew it was time to let go.

She was gone. She wasn't coming back.

And with the light of day, he knew he'd be forced to face that fact.

So there, in the semi-darkness of the bedroom that had been _theirs _for so many years, he found himself alone with a pen in his hand, a worn out old notebook resting in his lap. The pages were wrinkled at the edges, the cover rough, bent at the corners and weathered with age. A layer of dust coated the surface, untouched for most of the last year.

He'd long since retired from writing novels, though he still wrote for fun on occasion. And he still wrote for her, the words flowing almost effortlessly, still so inspired by her after all these years.

But tonight he knew, without a doubt, that these would be the last words he'd ever write.

_Dear Kate,_

_I don't know what to do anymore. You're not here. You're gone from this world forever. And after 49 years with you by my side, I'm just so lost. I can't remember a time when I wasn't in love with you. When I couldn't lean in and kiss you. When I didn't wake up next to you every morning, your body soft and warm against mine._

_It's so cold, Kate. So cold as I lie here in our bed, alone, without you. The air in the house is empty, desolate, and it's seeping into my bones, clenching my chest, shrouding my heart._

_And it hurts. I feel like someone sliced my chest open and left me here to bleed. I can't decide what's worse anymore; the stabbing pain in my heart or the dull numbness everywhere else. It's too much and too little all at the same time and I don't think I can go on like this. I know you'd want me to. I know you'd want me to live out the final years of my life to the fullest. You'd want me to be there for Alexis, for Lily and the boys and our grandkids. You'd want me to smile and laugh and find the joy in life – the joy you said I brought to you every day._

_I want that too. I want to live for you. I want to make you proud._

_But I don't know how. I don't know how to be that man anymore. My heart shattered the moment yours stopped beating and I don't know how to put it back together again. I don't know if I'll ever be able to._

_I'm sorry. I'm so sorry I'm letting you down. I'm sorry I can't carry on the way I know you'd have wanted me to. You know I always did believe that of the two of us, you were the strongest._

_Maybe someday I'll be able to find even the smallest semblance of that strength. Maybe I'll be able to find something to hold onto. For you, Kate, I promise to try._

_I don't know where you are now or what happens next, but if you can see me, if you can read these words, please know that I treasure every single moment I ever spent with you. I'm the luckiest guy in the world for being able to call myself your husband. For having the chance to love you and be loved by you in return._

_And no matter what happens, no matter where I end up, know that I will always carry you with me. In my words, in my memories, and in my heart._

_I love you, Kate._

_Always._

_Rick_

He stared at the page for a long time, eyes swimming over the black ink, the words blurring together through the tears that he no longer tried to hold back. His handwriting was much shakier than it used to be, his pen strokes less precise, but the words themselves were still there. He thought back to the millions of words he'd written over the years, not just as novels, but here in their collection of journals.

It was heartbreaking to know it was over, that this particular story had come to a close. He hoped someday in the future their children and grandchildren could draw comfort and hope and love from their story in the same way that his words had always been a source of comfort for Kate.

Kate.

He missed her. He would always miss her.

But here, within the pages of this notebook and the many others they'd filled through the years, she'd live on forever.

He pressed his fingers to his lips, felt a single tear slip from the corner of his eye as he brushed his fingertips softly against the page, released his final words to her into the never-ending silence of the room.

"I love you."

* * *

_Thoughts?_


	30. Chapter 30

_Thank you all for supporting me and sticking with me, not just through this fic but through Spiral Bound and the many years that passed between it and this sequel. I'm so glad you guys are still out there helping keep this fandom alive!_

_Thank you to everyone who ever reviewed, shared the links, tweeted encouragement, etc._

_Thank you to those of you who sent me suggestions; your ideas ultimately helped shape this story._

_And finally, thank you to Andy, my wonderful beta! I'm sorry I made you cry again with this chapter._

* * *

**April 19, 2061**

He found it a month after it happened.

He was going through her belongings, the wooden box where she always kept her most prized possessions; pictures, trinkets, gifts from her mother, many of the letters she'd written to him over the years. He was seated on the edge of the bed, the box open next to him as he read through her letters one by one, tears in his eyes as he soaked up her words. These things she'd left behind – her words to him – they were his lifeline.

He'd read through their journals, too, over the last month, devouring letter after letter late into the night when sleep eluded him, the bed too large, too empty, too cold without her. And so he sought comfort in words, in their story, all the way back to the very beginning. He'd never been able to capture Kate with words alone, but reading, remembering – it made him feel closer to her, erased some of the stark emptiness inside of him.

Castle refolded the letter in his hands, words from Kate from that summer fifty years ago; the last summer they'd ever spent apart. He was slipping it back into place when he stumbled upon a page he'd never seen before, a folded square in amongst the others.

This one looked newer, the paper less creased, less yellowed with age. And as he unfolded it, it became clear that the handwriting was different too. It was undoubtedly hers, but it wasn't quite as precise, the pen strokes slightly shaky. As though it'd been written much more recently. A glance at the date in the upper left-hand corner confirmed it had been.

With shaking fingers, Castle smoothed down the paper, squinting in the lamp-light as he forced his aging eyes to focus on the words.

_May 1st, 2059_

_Dear Castle,_

_I hope you never read this letter, because if you do it means I'm already gone. I hope it doesn't happen that way; it's not something I even like to think about. But in case it does, there are some things I want you to know, and one final request that I have._

_I know it won't be easy, but please, Babe. Please find the strength to go on, to keep living and writing and bringing comfort to others through your words and your smile and your kind heart. That was the most precious gift you ever gave to me, and I want it to live on in any way possible for as long as possible. I want others to know what a kind, loving, incredible man you are. But most of all, I want them to know what it's like to be loved by you, because there is nothing better._

_I don't know where I am now or what happened or if I'll ever see you again, but I do know that everything we've been through together has been an amazing adventure. We've laughed and cried, screamed and fought, loved and been loved. We've accomplished so much together and I want you to know I'm so proud of you and of us for all we've helped each other to become. For the family we raised, the wonderful life we created for ourselves._

_My existence would have been so much less without you, so unenriched and unfulfilled. I don't know how I can ever thank you enough for what you did for me, the way you stuck around when all I wanted was for you to leave. The way you fought for me when I didn't think there was anything worth fighting for. The way you coaxed me out of my shell and helped me to see the world again. The way you helped me realize I could be happy. The way you realized that happiness lay with us, together, when I was too stubborn to open my eyes and see what was right in front of me._

_You're the absolute best thing that's ever happened to me, Rick, and I'm eternally grateful that you are a part of my life._

_I'm not entirely sure what possessed me to write this letter today, but I hope that if you do end up reading it, it helps in some small way. I hope you can draw the same strength from my words that I've always drawn from yours._

_So here's to us, to the amazing times we had, all the wonderful years spent by each other's side, all the love we shared. I love you so much, Castle. Always have, always will._

_Love,  
Kate_

He lowered his hand shakily, the letter still clasped between his fingers, the paper hanging limply next to his thigh. The tears in his eyes were flowing freely now, running down his cheeks, dripping onto the soft cotton of his sweatpants, but he did nothing to stem the flow.

The last month had been miserable, the absolute worst time of his life. He'd lived with Kate for so long, existed side by side with her for so many years, that he no longer knew who he was without her. No longer knew how to wake up and make only one cup of coffee, how to climb into bed alone at night, the other half of the mattress cold and vacant.

He was so lost, drifting, nothing solid to hold onto. And he'd never in his life felt so empty.

But now he had her words. Something to fill his heart. Something to ground him, remind him of all the amazing memories, all that they were. All that he still had to live for.

And for the first time in a long time, he felt his heart unclench, the numbness begin to fade, a smile almost escaping. She wrote him a letter. She left him her words, a beautiful string of sentences that encompassed so many of the things he'd loved about her; her eloquence, her love of the written word, her intelligence and strength and tenacity, her passion for life and everything in it.

Her love.

* * *

It helped.

When Alexis came by later that day for dinner, she saw him smile for the first time in a month.

He showed up at Elena and Cora's dance recital that very weekend, and he moved more slowly than he used to, joints weary with exhaustion and age and the loss of his wife. But he perched on the bench between Jake and Alexis and cheered for his granddaughters with an exuberance she hadn't seen since Kate.

He still missed her terribly. They all did, and Alexis knew they always would. But whatever happened, whatever was responsible for this change in her dad, she was happy to finally see him living again, out in the world with a smile lifting the corners of his mouth.

Before they parted ways at the end of the game she hugged him tightly, whispered her happiness at seeing him here, watching him slowly find himself again. He thanked her, chest tight, the words caught in his throat. It still hurt, and there was still a gaping hole in his heart. There always would be. But for Kate, he could do this. For Kate, he could live again.

He'd never been able to deny her anything, after all.

"I'm proud of you, Dad," Alexis murmured as they separated a moment later, two sets of intense blue eyes meeting, unshed tears shimmering between them. "And I know that wherever Kate is now, she is too."

* * *

**END**


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